Temat: 75.50.Gg - Katalog OPAC zbiorów

Skocz do pozycji: 1.

Tytuł:: Magnonic Spectra of Ferromagnetic Composites Versus Magnetization Contrast
Autorzy:: Krawczyk, M.
Puszkarski, H.
Powiązania:: https://bibliotekanauki.pl/articles/1968941.pdf
Data publikacji:: 1998-05
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
Opis:: It had been shown recently that the calculated magnonic spectra of two-dimensional periodic ferromagnetic composites can present frequency ranges forbidden for the propagation of magnon excitations throughout the composite. However, those forbidden energy gaps were found to be highly sensitive to the exchange contrast between the component ferromagnetic materials but were very weakly sensitive to the contrast in spontaneous magnetizations of the two materials. Accordingly, in this paper we introduce a new mathematical definition of the exchange field acting in inhomogeneous medium. With this new definition the present theory gives magnonic spectra reasonably sensitive to magnetization contrast, as they should be from the physical viewpoint; moreover, the magnetization contrast now becomes a gap-creating factor as well.
Źródło:: Acta Physica Polonica A; 1998, 93, 5-6; 805-810
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 2.

Tytuł:: Conductivity and Magnetism of Magnetic Oxides
Autorzy:: Gehring, G. A.
Powiązania:: https://bibliotekanauki.pl/articles/2012877.pdf
Data publikacji:: 2000-01
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Pp
75.50.Gg
Opis:: In a stoichiometric oxide the energy for the magnetic ordering is due to superexchange. This depends on the virtual transfer of a d electron from the transition ion to the neighbouring oxygen. When the oxide is p-doped there are compensating holes on the oxygen or the transition ion becomes mixed valent. The oxide may then conduct. The same transfer integral enters both the expression for the antiferromagnetic superexchange and the band width of the mobile carriers. Thus materials with a large antiferromagnetic exchange energy will be expected to have a relatively wide conduction band in the doped state and hence to have a high conductivity. In this paper the difference is explored between the materials in which there is true antiferromagnetism and those which are ferrimagnetic. In the antiferromagnets the carriers must destroy the magnetic order as they move. This behaviour is well known from the cuprates. In ferrimagnets the carriers may be able to move entirely on one sublattice. This occurs in Fe$\text{}_{3}$O$\text{}_{4}$ and probably in the doped garnets. In the case where motion is on one sublattice then doping does not destroy the magnetism and there is a relatively small magnetoresistance. An interesting feature is that unlike the cuprates the ferrimagnets do not become good metals at any doping but exhibit hopping conductivity. We explain the apparent paradox that the best conductivity is actually observed in materials where the conduction is only allowed when the antiferromagnetism has been quenched and that the conductivity in ferrimagnets is low.
Źródło:: Acta Physica Polonica A; 2000, 97, 1; 175-184
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 3.

Tytuł:: Magnetic Properties of Zinc Doped Ferrites
Autorzy:: Abd El-Ati, M. I.
Kafafy, Aziz M.
Tawfik, A.
Powiązania:: https://bibliotekanauki.pl/articles/1887816.pdf
Data publikacji:: 1991-06
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.50.Dd
Opis:: A series of samples of the system Co$\text{}_{1-x}$Zn$\text{}_{x}$Fe$\text{}_{2}$O$\text{}_{4}$ (x = 0.0, 0.3, 0.4, 0.5 and 0.8) have been prepared by the usual ceramic technique. X-ray analysis shows that they are cubic spinel (single phase). The lattice parameter a and the bulk density D are measured for the samples. The substitution experiments replacing Co$\text{}^{2+}$ by Zn$\text{}^{2+}$ furnish new significant fact concerning the magnetic behaviour of ferrites. The magnetic strength of the magnetic ions on the Band A-sites can be varried relative to each other by the substitution of Zn$\text{}^{2+}$. The increase of density of the composition increases the magnetic interaction of the dipole moment at the B-sites.
Źródło:: Acta Physica Polonica A; 1991, 79, 6; 889-894
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 4.

Tytuł:: Single-Ion Rare Earth Anisotropy in ThMn$\text{}_{12}$-Type Compounds
Autorzy:: Stefański, P.
Powiązania:: https://bibliotekanauki.pl/articles/1931244.pdf
Data publikacji:: 1994-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Gw
75.50.Gg
Opis:: The single-ion rare earth anisotropy was investigated in ThMn$\text{}_{12}$-type compounds. For this purpose the crystal electric field parameter values were studied. In these compounds, described by formula RFe$\text{}_{12-x}$T$\text{}_{x}$, R = rare earth, T = Ti, V, Cr, Mo, W and Si, the T atoms have strong crystallographic site preference changing the local crystal electric field potential which "sees" the rare earth ion. The crystal electric field potentials A$\text{}_{2}^{0}$ were calculated considering this site preference. The summations were performed taking into account the nearest neighborhood of the rare earth ion according to the recent results of band structure calculations. The charges of the surrounding Fe and T atoms were established applying the chemical bond model proposed by Pauling. The absolute value of A$\text{}_{2}^{0}$ decreases when the content of vanadium increases in 8(i) position, which is in agreement with experimental data. Localization of Si atoms in 8(j) and 8(f) causes a decrease in A$\text{}_{2}^{0}$. The $\text{}^{155}$Gd Mössbauer spectroscopy data confirm this fact. Miedema's "macroscopic" atom model of cohesion in alloys was applied for interpretation of the role of T atoms in the isomer shift and volume effects.
Źródło:: Acta Physica Polonica A; 1994, 85, 3; 615-621
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 5.

Tytuł:: Effect of Fe substitution on structural and magnetic properties of NiCr₂O₄
Autorzy:: Mohanty, P.
Prinsloo, A.
Sheppard, C.
Roos, W.
Powiązania:: https://bibliotekanauki.pl/articles/1048307.pdf
Data publikacji:: 2018-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.60.-d
Opis:: At room temperature, the normal oxide spinel NiCr₂O₄ is tetragonally distorted and crystallizes in the I4₁/amd space group due to cooperative Jahn-Teller ordering driven by the orbital degeneracy of tetrahedral Ni²⁺. The ferrimagnetic Curie temperature (T_{C}) for NiCr₂O₄ is 74 K. The magnetic moments of NiCr₂O₄ are composed of a ferrimagnetic (longitudinal) and an antiferromagnetic (transverse) component. Exchange interaction between the magnetic cations influences the overall magnetic properties of the compound. Present work focuses on the modification of structural and magnetic properties upon substituting Fe at Cr site in NiCr₂O₄ with the motivation of changing the magnetic exchange interaction. In order to do so, single phase Ni(Cr_{0.5}Fe_{0.5})₂O₄ samples were prepared by co-precipitation techniques, while controlling the pH of precipitation. Upon Fe substitution, crystal structure was not affected much contrary to the earlier reports. In order to determine the oxidation state of each elements X-ray photoelectron spectroscopy (XPS) was performed. T_{C} was found to increase dramatically above 300 K, confirmed both from temperature and field dependent dc-magnetization studies.
Źródło:: Acta Physica Polonica A; 2018, 133, 3; 574-577
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 6.

Tytuł:: Magnetic Properties of $Ni_{0.3}Zn_{0.7}Fe_2O_4$ Ferrites with Iron Ions Partly Substituted by Europium
Autorzy:: Ušák, E.
Ušáková, M.
Šoka, M.
Vašut, D.
Powiązania:: https://bibliotekanauki.pl/articles/1398263.pdf
Data publikacji:: 2017-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.30.-m
Opis:: This work is devoted to the study of the impact of the substitution of iron by Eu on the properties of magnetically soft $Ni_{0.3}Zn_{0.7}Eu_{x}Fe_{2-x}O_4$ ferrites aimed at enhancement of the knowledge related to the behavior of such materials in dependence on the amount of iron substitution. Our latest studies focused on the materials having similar chemical composition gave a hint of some possible approaches to manage the resulting magnetic properties in a precisely controlled way by the combination of several factors; choice of initial chemical composition of non-substituted ferrite, selection of substituted and substituting element, variations of final chemical composition, modifications of fabrication technology (sintering temperature and time), etc.
Źródło:: Acta Physica Polonica A; 2017, 131, 4; 717-719
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 7.

Tytuł:: Magnetism in $RCo_{2}$ (R = Dy, Ho, Er, Tm) Under Hydrostatic Pressure
Autorzy:: Prchal, J.
Šebesta, J.
Valenta, J.
Míšek, M.
Turčinková, D.
Lapčák, L.
Prokleška, J.
Kratochvílová, M.
Sechovský, V.
Powiązania:: https://bibliotekanauki.pl/articles/1369111.pdf
Data publikacji:: 2014-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.20.En
75.50.Gg
Opis:: The short-range parimagnetic configurations, observed in the heavy rare-earth $RCo_{2}$ compounds in paramagnetic range far above the Curie temperature $T_{C}$, consist in formation of ferromagnetic cobalt clusters antiferromagnetically coupled to the neighboring R magnetic moments. The characteristic temperature of the onset of parimagnetism $T_{f}$ is very sensitive to changes of external conditions like pressure or composition. The pressure coefficients $∂T_{f}$/∂p and $∂T_{C}$/∂p are comparable, indicating a close connection of underlying mechanisms. Our recent measurements indicate systematic evolution of the pressure coefficients with spanning the rare-earth series from Dy through Tm in $RCo_{2}$ with a specific case $TmCo_{2}$.
Źródło:: Acta Physica Polonica A; 2014, 126, 1; 288-289
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 8.

Tytuł:: About the Role of Fe-Ions in the Formation of Magnetocaloric Effect in $Ho(Co_{1-x}Feₓ)₂$ Compounds
Autorzy:: Anikin, M.
Tarasov, E.
Kudrevatykh, N.
Osadchenko, V.
Zinin, A.
Powiązania:: https://bibliotekanauki.pl/articles/1387987.pdf
Data publikacji:: 2015-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Sg
75.50.Gg
Opis:: A study of crystalline structure, magnetic and magnetocaloric properties of $Ho(Co_{1-x}Feₓ)₂$ (x = 0.09, 0.12) intermetallic compounds has been undertaken. Phase composition was controlled by X-ray diffraction analysis. Magnetic properties were measured within the temperature range 4.2-350 K in magnetic fields up to 7 T. Magnetic ordering temperatures corresponding to paramagnetic-ferrimagnetic phase transitions were found to be 199 K and 258 K respectively. Temperature dependences of heat capacity for these compounds have been inferred for the temperature interval 77-340 K. Comparison of magnetocaloric effect (MCE) values determined by direct measurement and by calculation was carried out as well. It was found that significant MCE peak broadening occurs for higher iron concentration in the compound.
Źródło:: Acta Physica Polonica A; 2015, 127, 2; 635-637
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 9.

Tytuł:: The Influence of Compressive Stresses on the Properties of Inductive Electronics Components
Autorzy:: Salach, J.
Nowak, P.
Powiązania:: https://bibliotekanauki.pl/articles/1031009.pdf
Data publikacji:: 2018-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.30.-m
Opis:: This paper presents results of investigation of stress influence on magnetic characteristics of ferrite ring cores for inductive electronics components. Ring-shaped cores were made of Ni-Zn ferrite designed for anti-lung filter cores. The results of the study indicate a significant impact of external forces stresses on the magnetic properties of ferrite cores. Such changes are very important due to their influence on the correct operation of the induction components.
Źródło:: Acta Physica Polonica A; 2018, 133, 4; 1053-1055
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 10.

Tytuł:: Presence of Parimagnetism in $Ho(Co_{1-x}Si_{x})_{2}$ Under Hydrostatic Pressure
Autorzy:: Valenta, J.
Prchal, J.
Kratochvílová, M.
Míšek, M.
Sechovský, V.
Powiązania:: https://bibliotekanauki.pl/articles/1372511.pdf
Data publikacji:: 2014-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.20.En
75.50.Gg
Opis:: A new configuration of cobalt magnetic moments with respect to rare-earth ones on local level, named as parimagnetism, surviving above the Curie temperature was determined few years ago for $ErCo_{2}$. Occurrence of parimagnetism has recently been confirmed also for $HoCo_{2}$. In this paper we present results manifesting considerable composition and hydrostatic-pressure influence on characteristic temperatures of magnetism in $Ho(Co_{1-x}Si_{x})_{2}$ compounds and draw a preliminary scenario analyzing the exchange interactions involved.
Źródło:: Acta Physica Polonica A; 2014, 126, 1; 406-408
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 11.

Tytuł:: Magnetic Phase Transitions and Thermal Properties of $Ho(Co_{1-x}Si_x)_2$ Compounds
Autorzy:: Vasylyev, D.
Prokleška, J.
Sechovský, V.
Powiązania:: https://bibliotekanauki.pl/articles/1813682.pdf
Data publikacji:: 2008-01
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Sg
75.50.Gg
Opis:: The specific heat of $HoCo_2$ and $Ho(Co_{0.95}Si_{0.05})_2$ was measured as a function of temperature in several constant magnetic fields up to 8 T. A data analysis allowed us to determine the isothermal entropy change and the magnetocaloric effect in a wide temperature range. The considerable values of the magnetocaloric effect in the vicinity of the magnetic ordering transition are qualifying both compounds as suitable for magnetic refrigeration purposes. The magnetic phase transition temperature $(T_C)$ increases from 77 K for $HoCo_2$ to 103 K for $Ho(Co_{0.95}Si_{0.05})_2$ while the large magnetocaloric effect in the vicinity of TC is maintained, which demonstrates possible ways of tuning the operating temperatures of the magnetic refrigerant.
Źródło:: Acta Physica Polonica A; 2008, 113, 1; 347-350
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 12.

Tytuł:: Spin Reorientation and Exchange Coupling in the Dy$\text{}_{1-x}$Er$\text{}_{x}$Fe$\text{}_{10}$Si$\text{}_{2}$ Compounds
Autorzy:: Stefański, P.
Kowalczyk, A.
Skoryna, D.
Szlaferek, A.
Wrzeciono, A.
Powiązania:: https://bibliotekanauki.pl/articles/1929845.pdf
Data publikacji:: 1994-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Gw
75.50.Gg
Opis:: The structural and magnetic properties of Dy$\text{}_{1-x}$Er$\text{}_{x}$Fe$\text{}_{10}$Si$\text{}_{2}$ are investigated. X-ray analysis reveals that these compounds are of the tetragonal ThMn$\text{}_{12}$ structure. In this structure the rare earth atoms occupy one crystallographic position 2(a). The unit cell contains 26 atoms. The spin reorientation temperature, T$\text{}_{SR}$, was measured from the temperature dependence of the initial susceptibility using an ac bridge of mutual inductance of the Harsthorn type. Dy$\text{}^{+3}$ and Er$\text{}^{+3}$ have opposite contributions to the entire magnetic anisotropy. The spin reorientation temperature is found to be about 271 K in DyFe$\text{}_{10}$Si$\text{}_{2}$ and 48 K in ErFe$\text{}_{10}$Si$\text{}_{2}$. The values are discussed applying the crystal field model. The value of the rare earth-transition metal exchange coupling constant J$\text{}_{RFe}$/k$\text{}_{B}$ derived from the mean-field model analysis of the Curie temperature is about -13 K. The Fe-Fe exchange integral is much higher and is equal to about 75 K.
Źródło:: Acta Physica Polonica A; 1994, 85, 2; 259-262
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 13.

Tytuł:: Ground State Properties of Tb$\text{}^{3+}$ Ion in TbNi$\text{}_{10}$Si$\text{}_{2}$
Autorzy:: Stefański, P.
Suski, W.
Wochowski, K.
Mydlarz, T.
Powiązania:: https://bibliotekanauki.pl/articles/1964565.pdf
Data publikacji:: 1997-08
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Gw
75.50.Gg
Opis:: Ground state properties of Tb$\text{}^{3+}$ ion were investigated in the tetragonal ThΜn$\text{}_{12}$-type TbNi$\text{}_{10}$Si$\text{}_{2}$ compound on the basis of temperature dependence of the paramagnetic susceptibility and magnetization measurements. The rare earth temperature dependence of the susceptibility was calculated using the Van Vleck equation. The Γ$\text{}_{t5}^{(1)}$ doublet is suggested to be a ground state separated by 9 K from the first excited singlet Γ$\text{}_{t1}^{(2)}$. The magnetic moment associated with the ground state doublet agrees with saturation magnetization data at 4.2 K. The overall crystal field splitting is estimated to be 105 K.
Źródło:: Acta Physica Polonica A; 1997, 92, 2; 281-284
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 14.

Tytuł:: Mechanisms of the Magneto-Optical Activity of Rare-Earth Ions in Rare-Earth Iron Garnet Single Crystals
Autorzy:: Tsidaeva, N.
Abaeva, V.
Magkoev, T.
Powiązania:: https://bibliotekanauki.pl/articles/1490761.pdf
Data publikacji:: 2012-01
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
78.20.Ls
Opis:: The magnetic and magneto-optical properties of the typical representatives of three rare-earth iron garnets (RIG) groups: with heavy rare-earth elements Yb, Er, Dy, Tb; with elements from the middle of lanthanide series Gd, Sm, and with light rare-earth element Nd are presented. In contradistinction to other work on the Faraday rotation, which were done only at 1152 nm (8696 $cm^{-1}$), here we present FR spectra obtained in the energy region 5500-20000 $cm^{-1}$ with high optical resolution. The investigations have been done at temperatures of 5, 82, 130, 295 K using magnetic field up to 25 kOe applied parallel to the [111] crystallographic axis of the crystals. It has been shown that the contribution proportional to the magnetic field and independent of temperature to the mixing of the ground state multiplets exceeds the paramagnetic contribution in YbIG, ErIG, GdIG, SmIG. In Tb and Dy iron garnets contributions from the two mechanisms have opposite signs, and the paramagnetic mechanism gives the greatest contribution to the Faraday rotation. Nevertheless, the contribution of the diamagnetic mechanism, caused by the influence of the exchange field in the iron sublattices on rare-earth ions, is significant, and it is necessary to take it into account. Anomalously large magneto-optical activity is observed in NdYIG. This is the result of contributions of the same sign and approximately equal in magnitude from the paramagnetic and diamagnetic mechanisms.
Źródło:: Acta Physica Polonica A; 2012, 121, 1; 74-77
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 15.

Tytuł:: Hyperfine Field in YIG with Charged Substitution
Autorzy:: Kohout, J.
Štĕpánková, H.
Englich, J.
Novák, P.
Kučera, M.
Nitsch, K.
Powiązania:: https://bibliotekanauki.pl/articles/2013158.pdf
Data publikacji:: 2000-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 76.60.-k
75.50.Gg
Opis:: $\text{}^{57}$Fe NMR spectra were measured on thin films of yttrium iron garnet with divalent (Ca$\text{}^{2+}$) and tetravalent (Ge$\text{}^{4+}$) cation substitutions using the spin echo technique at 4.2 K. A series of Y$\text{}_{3-x}$Ca$\text{}_{x}$Fe$\text{}_{5-x}$Ge$\text{}_{x}$O$\text{}_{12}$ samples with 0 ≤ x ≤ 0.0 5 was prepared by an epitaxial growth from BaO/B$\text{}_{2}$O$\text{}_{3}$/BaF$\text{}_{2}$ flux on gadolinium gallium garnet substrate. Satellite lines corresponding to the iron ions having the Ge$\text{}^{4+}$ and Ca$\text{}^{2+}$ in their neighbourhood were identified. The sample with the germanium content of x(Ge) = 0.004 and (110) substrate orientation was used for a detailed study: NMR spectra of this sample were measured in an external magnetic field of 0.1 T applied along several directions in the plane of the film. The modification of the isotropic part and the anisotropy tensor of the hyperfine interaction caused by the Ge$\text{}^{4+}$ substituent were obtained from the experimental data. The results were compared with those previously reported for trivalent substitution (Ga$\text{}^{3+}$).
Źródło:: Acta Physica Polonica A; 2000, 97, 3; 519-522
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 16.

Tytuł:: $\text{}^{57}$Fe Hyperfine Field Anisotropy in Ferrites and its Relation to the Non-Uniformity of the Ionic Surrounding
Autorzy:: Štepánková, H.
Englich, J.
Kohout, J.
Powiązania:: https://bibliotekanauki.pl/articles/2013366.pdf
Data publikacji:: 2000-05
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 76.60.-k
75.50.Gg
Opis:: The hyperfine field anisotropy tensors, obtained from analysis of $\text{}^{57}$Fe NMR spectra for iron sites in various magnetic oxides (barium hexaferrite, lithium spinel, magnetite and yttrium-iron garnet) were used to investigate the relation between the hf anisotropy and surrounding ionic arrangement. While a reasonable correlation has been found when the distribution of the nearest cations was considered, no correlation was obtained between the hyperfine field anisotropy and the positions of the nearest oxygen anions.z
Źródło:: Acta Physica Polonica A; 2000, 97, 5; 757-760
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 17.

Tytuł:: Field-Induced Slow Magnetic Relaxation in Mn₉W₆ Cluster-Based Compound
Autorzy:: Konieczny, P.
Pełka, R.
Chorazy, S.
Podgajny, R.
Sieklucka, B.
Wasiutyński, T.
Powiązania:: https://bibliotekanauki.pl/articles/1032251.pdf
Data publikacji:: 2017-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Xx
75.40.Cx
75.50.Gg
Opis:: Magnetic measurements of a three-dimensional (3D) molecular magnet built of Mn₉[W(CN)₈]₆ clusters have been carried out to study its static and dynamic properties. Measurements of ac susceptibility in the presence of static magnetic field revealed slow magnetic relaxations. It was found that for the 120 Hz wave frequency the optimal static field which maximizes the imaginary component of the ac susceptibility is about 500 Oe.
Źródło:: Acta Physica Polonica A; 2017, 131, 4; 884-886
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 18.

Tytuł:: Open Source Implementation of Different Variants of Jiles-Atherton Model of Magnetic Hysteresis Loops
Autorzy:: Szewczyk, R.
Cheng, P.
Powiązania:: https://bibliotekanauki.pl/articles/1030747.pdf
Data publikacji:: 2018-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Bb
75.50.Gg
75.60.Ej
Opis:: Jiles-Atherton model is one of the most advanced and most popular models of magnetic hysteresis loop. However, this model is considering different physical phenomena and computational issues. As a result, cross-validation of the results of modelling performed by different authors became difficult. For this reason, the open-source MATLAB/OCTAVE based implementation of Jiles-Atherton model was developed. Proposed implementation covers isotropic model of magnetic hysteresis loops as well as uniaxial and grain oriented electrical steel anisotropy. Moreover, the corrections proposed by Venkataraman together with different approaches to derivative of the anhysteretic magnetization are considered. Developed library is freely available together with the examples of magnetic hysteresis loops. As a result, it can be the base for further development of Jiles-Atherton model for better understanding of magnetization process as well as modelling the inductive components.
Źródło:: Acta Physica Polonica A; 2018, 133, 3; 654-656
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 19.

Tytuł:: Modelling of the Magnetic Characteristics of Isotropic and Anisotropic Materials for Sensor Applications
Autorzy:: Szewczyk, R.
Powiązania:: https://bibliotekanauki.pl/articles/1813527.pdf
Data publikacji:: 2008-01
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.60.Ej
75.50.Gg
75.50.Kj
Opis:: The following paper presents the results of modelling of the magnetic characteristics of isotropic (Ni-Zn ferrite) and anisotropic material ($Fe_{40}Ni_{38}Mo_4B_{18}$ amorphous alloy in as quenched state), both useful for sensor applications. For the modelling an extended Jiles-Atherton model was used. Extension of the model connects model's parameter k, describing average energy required to break pinning site, with magnetic state of the material. Such extension of the model is reasonable from the physical point of view. Good agreement between experimental data and modelling confirms that the extended Jiles-Atherton model creates the possibility of modelling of magnetic characteristics of both isotropic and anisotropic magnetic cores.
Źródło:: Acta Physica Polonica A; 2008, 113, 1; 67-70
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 20.

Tytuł:: Biogenic Magnetite Nanoparticle Ensemble Use in MRI Diagnostics
Autorzy:: Strbak, O.
Krafcik, A.
Teplan, M.
Gogola, D.
Kopcansky, P.
Frollo, I.
Powiązania:: https://bibliotekanauki.pl/articles/1202318.pdf
Data publikacji:: 2014-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.50.Tt
87.61.-c
Opis:: We present a simple analytical tool, which allows the calculation of the MRI diagnostics feasibility of the biogenic magnetite nanoparticles. Elevated levels of these particles are usually linked to the pathological processes, especially to neurodegenerative disorders. We showed theoretically that the biogenic magnetite itself is not sufficient for the non-invasive diagnostics and must be extended with the total iron incorporated in other biological structures.
Źródło:: Acta Physica Polonica A; 2014, 126, 1; 388-389
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 21.

Tytuł:: The Effect of a Random Crystal-Field on the Mixed Ising Spins (1/2, 3/2)
Autorzy:: Bahmad, L.
Benayad, M.
Benyoussef, A.
El Kenz, A.
Powiązania:: https://bibliotekanauki.pl/articles/1504480.pdf
Data publikacji:: 2011-06
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 05.50.+q
75.10.Hk
75.50.Gg
Opis:: We study the magnetic properties of a mixed Ising ferrimagnetic system, in which the two interacting sublattices have spins σ,(±1/2) and spins S,(±3/2,±1/2) in the presence of a random crystal field, with the mean field approach. The results obtained, using mean field approach and Monte Carlo simulation, show the appearance of a new ferrimagnetic phase, namely the partly ferrimagnetic phase ($m_{σ}$ = -1/2 , $m_{S}$ = +1). Consequently, three topologically different types of phase diagrams have been given by mean field approach. The effect of increasing the exchange interaction parameter J, at very low temperature is also investigated.
Źródło:: Acta Physica Polonica A; 2011, 119, 6; 740-746
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 22.

Tytuł:: Semiconducting Properties of $Cu_5SbO_6$
Autorzy:: Groń, T.
Filipek, E.
Dąbrowska, G.
Duda, H.
Mazur, S.
Kukuła, Z.
Pawlus, S.
Powiązania:: https://bibliotekanauki.pl/articles/1409627.pdf
Data publikacji:: 2012-12
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Pp
72.20.Pa
75.50.Gg
Opis:: Thermoelectric power, electrical resistivity, I-V characteristics, relative electrical permittivity, dc magnetization and ac magnetic susceptibility measurements carried out on $Cu_5SbO_6$ showed p-type semiconducting behaviour with the activation energy of 0.24 eV as well as ferrimagnetic order with the Néel temperature of 5.2 K. The effective magnetic moment of 5.857 $μ_{B}$/f.u. revealed the orbital contribution to the magnetic moment. Large value of the relative electrical permittivity indicated that the $Cu^{2+}$ ions with the unscreened and unfilled electron shells are responsible for the polarizability and forming of electric dipoles.
Źródło:: Acta Physica Polonica A; 2012, 122, 6; 1105-1107
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 23.

Tytuł:: Structure of Iron Oxide Nanoparticles Studied by $\text{}^{57}Fe$ NMR
Autorzy:: Křišťan, P.
Chlan, V.
Štěpánková, H.
Řezníček, R.
Görnert, P.
Payer, P.
Powiązania:: https://bibliotekanauki.pl/articles/1378149.pdf
Data publikacji:: 2014-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 76.60.-k
75.50.Gg
75.50.Tt
Opis:: In this work we apply nuclear magnetic resonance (NMR) spectroscopy of $\text{}^{57}Fe$ nuclei for investigation of submicron and nanocrystalline iron oxide systems. The studied iron oxide particles are obtained from ferrous hydroxide gels (prepared from $FeCl_{2}$ and KOH) by aging at elevated temperatures (90 °C) with $KNO_{3}$ as oxidant. The $\text{}^{57}Fe$ NMR spectra of the samples are measured in temperature range 4.2-370 K in a zero external magnetic field. Signals of $\text{}^{57}Fe$ nuclei assigned to tetrahedral and octahedral iron sites are well resolved. The NMR spectra and their temperature dependences are compared with those of stoichiometric and nonstoichiometric magnetite single crystals, as well as with samples of maghemite.
Źródło:: Acta Physica Polonica A; 2014, 126, 1; 138-139
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 24.

Tytuł:: Magnetic Properties of Divalent (Ni,Sn,Zn)- Tetravalent (Ru,Sn) Ionic Mixtures of Substituted Ba Ferrite
Autorzy:: Sláma, J.
Grusková, A.
González Angeles, A.
Šoka, M.
Dosoudil, R.
Powiązania:: https://bibliotekanauki.pl/articles/1367766.pdf
Data publikacji:: 2014-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.50.Vv
77.22.Ej
Opis:: The drop of coercivity, while preserving the saturation magnetic polarisation $J_{S}$ of substituted M-type Ba hexaferrites with composition $BaFe_{12-2x}(Me_{1}Me_{2})_{x}O_{19}$, was studied. Divalent $Me_{1}$=Ni, Zn, Sn and tetravalent $Me_{2}$=Ru, Sn ionic combinations were used in various compounds. Mössbauer spectroscopy was used to reveal sites of replacement of the $Fe^{3+}$ ions by $Ru^{4+}$ and $Sn^{4+}$. The $Ni^{2+}$, $Zn^{2+}$ and $Sn^{2+}$ occupation sites were identified as well. Strong drop of coercivity difference Δ $H_{c}(x)$ near x=0.1 and slight decrease of Δ $H_{c}(x)$ close to x=0.3 was obtained for suitable coupling of $Me_{1}^{2+}$ and $Me_{2}^{4+}$ ions.
Źródło:: Acta Physica Polonica A; 2014, 126, 1; 172-173
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 25.

Tytuł:: Elimination of Magnetic Nanoparticles with Various Surface Modifications from the Bloodstream in vivo
Autorzy:: Tomasovicova, N.
Khmara, I.
Koneracka, M.
Zavisova, V.
Kubovcikova, M.
Antal, I.
Kovac, J.
Muckova, M.
Kopcansky, P.
Powiązania:: https://bibliotekanauki.pl/articles/1032816.pdf
Data publikacji:: 2017-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.50.Tt
87.85.jj
Opis:: The magnetic nanoparticles with the core diameter 10 nm stabilized by sodium oleate and bovine serum albumin in phosphate buffer have been modified by different biocompatible substances such as poly(ethylene glycol) (PEG), dextran (DEX), and polyvinylpyrrolidone (PVP). Prepared biocompatible magnetic fluids were characterized to obtain the particle size distribution using scanning electron microscopy and the dynamic light scattering method. To study the elimination of different modified magnetic nanoparticles from bloodstream, the biocompatible samples were applied intravenously to the mice bloodstream with further blood specimens collecting in given time intervals. Magnetic moment of the lyophilized blood samples was measured by SQUID magnetometer. Time dependence of magnetic moment of magnetic nanoparticles and magnetic nanoparticles modified by DEX, PEG and PVP normalized to the Fe₃O₄ showed that the circulation time of magnetic nanoparticles in the bloodstream depends on the substance used for modification. The unmodified magnetic nanoparticles were trapped by reticuloendothelial system within 1 h while magnetic nanoparticles modified by DEX, PEG and PVP circulated in blood up to 3 h.
Źródło:: Acta Physica Polonica A; 2017, 131, 4; 1159-1161
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 26.

Tytuł:: Structural characterization and magnetic properties of CuCr₂Te₄ spinel obtained by mechanical alloying and heat treatment
Autorzy:: Karolus, M.
Maciążek, E.
Panek, J.
Kubisztal, M.
Groń, T.
Powiązania:: https://bibliotekanauki.pl/articles/1154138.pdf
Data publikacji:: 2016-10
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.50.Tt
81.10.Jt
Opis:: CuCr₂Te₄ can be obtain by mechanical alloying followed by heat treatment. The obtained phase crystallizes in the spinel-type structure of the space group Fd3m. The calculated crystallite size equals to 100 nm. Magnetic susceptibility measurements showed ferrimagnetic order below 21 K.
Źródło:: Acta Physica Polonica A; 2016, 130, 4; 859-861
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 27.

Tytuł:: Reappearance of Antiferromagnetic Order in $Nd_{0.9}Ca_{0.1}BaCo_{2}O_{5+δ}$ for δ > 0.51
Autorzy:: Piętosa, J.
Kolesnik, S.
Puźniak, R.
Dabrowski, B.
Powiązania:: https://bibliotekanauki.pl/articles/1374353.pdf
Data publikacji:: 2014-10
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Kz
75.50.Gg
62.50.-p
Opis:: The absence of the antiferromagnetic order in $Nd_{0.9}Ca_{0.1}BaCo_2O_{5.5}$ has been found to remain unchanged by applying a hydrostatic pressure of 10 kbar. In magnetic studies of polycrystalline $Nd_{0.9}Ca_{0.1}BaCo_2O_{5+δ}$ (δ=0.07-0.69), we have found a reappearance of the antiferromagnetic phase, caused by an increase in oxygen index δ above 0.51 related to extra oxygen ions addition into the $NdO_{δ}$ plane. For the samples with δ=0.555 and 0.59, a coexistence of well developed antiferromagnetic phase with ferrimagnetic one is evidenced.
Źródło:: Acta Physica Polonica A; 2014, 126, 4a; A-50-A-52
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 28.

Tytuł:: Synthesis and Magnetic Properties of $CuCr_{1.65}Se_4$ Nanoparticles
Autorzy:: Maciążek, E.
Panek, J.
Kubisztal, M.
Karolus, M.
Groń, T.
Duda, H.
Powiązania:: https://bibliotekanauki.pl/articles/1376067.pdf
Data publikacji:: 2014-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.50.Tt
81.10.Jt
Opis:: $CuCr_{1.65}Se_{4}$ nanoparticles crystallize in the monoclinic $Cr_{2}Se_{3}$-type structure of the space group I2/m. The average crystallite size basing on the line broadening is less than 10 nm. With decrease of the size of grains a change from ferromagnetic to ferrimagnetic order, a lack of the magnetization saturation and a strong spin-orbit coupling visible in the large value of the Landé factor $g_{χ}$ = 2.72 are observed. The change in magnetic order is caused by the change of the crystalline symmetry from the cubic phase to monoclinic one.
Źródło:: Acta Physica Polonica A; 2014, 126, 5; 1137-1139
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 29.

Tytuł:: Hopkinson effect in soft and hard magnetic ferrites
Autorzy:: Sláma, J.
Ušáková, M.
Šoka, M.
Dosoudil, R.
Jančárik, V.
Powiązania:: https://bibliotekanauki.pl/articles/1053131.pdf
Data publikacji:: 2017-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.30.Kz
75.30.Cr
Opis:: The dependences of the susceptibility of selected spinel and hexagonal ferrites on temperature are analyzed. The susceptibility shows a peak just below the Curie temperature T_{C} due to the Hopkinson effect during the heating. The appearance of this effect is associated with a transition from the region of stable magnetization state to superparamagnetic relaxations of the magnetic particles. It is in contrast to other explanations of the Hopkinson effect. These results are compared with measured particles size and with scanning electron microscope micrographs of both types of ferrites.
Źródło:: Acta Physica Polonica A; 2017, 131, 4; 762-764
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 30.

Tytuł:: Magnetism in $NdMnO_{3+δ}$ Studied by the Single Crystal Neutron Diffraction
Autorzy:: Mihalik, M.
Maťaš, S.
Vavra, M.
Powiązania:: https://bibliotekanauki.pl/articles/1368766.pdf
Data publikacji:: 2014-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.20.-g
75.30.-m
75.50.Gg
Opis:: We present the single crystal neutron diffraction experiment performed on the $NdMnO_{3+δ}$ compound. The aim of the experiment was to study/revisit the magnetic structure of the compound. We have confirmed the ordering of Mn sublattice below $T_{N}$=85.5 K and confirmed that the Nd sublattice orders below $T_{1}$ ≈ 20 K with Nd moments aligned parallel to the b-axis.
Źródło:: Acta Physica Polonica A; 2014, 126, 1; 284-285
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 31.

Tytuł:: The Effects of the Random Transverse Crystal Field on the Spin-1 Model
Autorzy:: Albayrak, E.
Powiązania:: https://bibliotekanauki.pl/articles/1399269.pdf
Data publikacji:: 2015-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.10.Hk
75.30.Kz
75.50.Gg
Opis:: The effects of random transverse crystal field are investigated in the mean-field approximation on the spin-1 model. The transverse crystal field is applied on a lattice in a bimodal random distribution with a tunable parameter adjusting the strength of one mode with respect to the other one. Then, the phase diagrams are calculated on the reduced temperature-transverse crystal field planes for given values of probability p and coordination number q at zero external magnetic field h. It was found that the model gives both second- and first-order phase transitions and tricritical points which is a well-known behavior of the spin-1 model. In addition, the model also yields critical end points and end points for the first-order phase transition lines for appropriate p values.
Źródło:: Acta Physica Polonica A; 2015, 127, 3; 818-822
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 32.

Tytuł:: Giant Magnetoelectricity in Aluminium Substituted Y-Hexaferrites
Autorzy:: Novák, P.
Chlan, V.
Knížek, K.
Powiązania:: https://bibliotekanauki.pl/articles/1506886.pdf
Data publikacji:: 2010-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.85.+t
71.20.Ps
75.50.Gg
Opis:: The electron structure of Al containing Y-hexaferrite that exhibits the giant magnetoelectricity is calculated. Results show strong preference of Al for octahedral sites. Orbital moment of some of the iron ions is found to be unusually large.
Źródło:: Acta Physica Polonica A; 2010, 118, 5; 723-724
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 33.

Tytuł:: Cation Distribution in Fe$\text{}_{3(1-\delta)}$O$\text{}_{4}$ and Low Level Doped Fe$\text{}_{3-x}$M$\text{}_{x}$O$\text{}_{4}$, M=Ti, Zn, Al
Autorzy:: Kąkol, Z.
Kozłowski, A.
Sabol, J.
Metcalf, P.
Honig, J. M.
Powiązania:: https://bibliotekanauki.pl/articles/1861287.pdf
Data publikacji:: 1994-01
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 72.80.Ga
75.30.Cr
75.50.Gg
Opis:: Systematic magnetic saturation moment and electrical resistivity measurements of the Fe$\text{}_{3(1-\delta)}$O$\text{}_{4}$ and Fe$\text{}_{3-x}$M$\text{}_{x}$O$\text{}_{4}$ (M = Ti, Zn, Al) are presented. Cation distributions for low level doping are proposed and compositional dependencies of the Verwey transition temperature are determined. The latter show striking similarities in their dependence on cation vacancies and dopant concentration for any extraneous cations. These data are the basis for the analysis of the correlation between the presented cations distributions and the Verwey transition.
Źródło:: Acta Physica Polonica A; 1994, 85, 1; 223-227
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 34.

Tytuł:: Complex Permeability of LiZn/MnZn/PVC Composite Materials
Autorzy:: Dosoudil, R.
Ušáková, M.
Grusková, A.
Sláma, J.
Powiązania:: https://bibliotekanauki.pl/articles/1535468.pdf
Data publikacji:: 2010-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 72.80.Tm
75.50.Gg
76.50.+g
Opis:: The effect of particle content, size, and the fraction ratio of the double LiZn/MnZn ferrite filler in hybrid LiZn/MnZn/PVC composites on the frequency dispersion of complex permeability has been studied in the 1 MHz-3 GHz frequency range. The obtained relaxation type of permeability dispersion is due to the domain wall resonance, the natural ferromagnetic resonance, and the relaxation of magnetization rotation. The permeability and resonance/relaxation frequency of composites seem to be strongly affected by the change of particle content and fraction ratio of the double ferrite filler rather than by particle size.
Źródło:: Acta Physica Polonica A; 2010, 118, 5; 1049-1050
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 35.

Tytuł:: Frequency Variation of Complex Permeability in Dual Ferrite Filler - Single Polymeric Matrix Composites
Autorzy:: Dosoudil, R.
Ušáková, M.
Sláma, J.
Grusková, A.
Powiązania:: https://bibliotekanauki.pl/articles/1813959.pdf
Data publikacji:: 2008-01
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 72.80.Tm
75.50.Gg
76.50.+g
Opis:: The frequency dependences of complex initial permeability for triple-component composite materials based on two different types of ferrite filler (MnZn and NiZn ferrite) and a nonmagnetic polymeric matrix (PVC) were studied in the frequency range of 10 kHz-1 GHz. The frequency dispersion of permeability is discussed by means of a dynamic model based on the superposition of the two types of magnetic resonance, the resonance of vibrating domain walls and the resonance of precessing magnetic moments in domains.
Źródło:: Acta Physica Polonica A; 2008, 113, 1; 621-624
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 36.

Tytuł:: Effect of Pressure on Magnetic Properties of Hexacyanochromates
Autorzy:: Mitróvá, Z.
Maťaš, S.
Mihalik, M.
Zentková, M.
Arnold, Z.
Kamarád, J.
Powiązania:: https://bibliotekanauki.pl/articles/1813813.pdf
Data publikacji:: 2008-01
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Cr
75.50.Ee
75.50.Gg
75.50.Xx
Opis:: We present the study of pressure effect on magnetic properties of $TM^{2+}_3[Cr^{III}(CN)_6]_2 \cdot nH_2O$ ferrimagnets and ferromagnets (TM = Cr and Co) under pressures up to 0.9 GPa. Applied pressure strengthens super-exchange interaction in $Cr^{2+}$-prussian blue analogues with dominant antiferromagnetic interaction $J_{AF}$ leading to increase in the Curie temperature $T_C$ (ΔT_c/Δp = 29.0 K/GPa) and reduces $T_C$ of $Co^{2+}$-prussian blue analogues with dominant ferromagnetic interaction $J_F$ (Δ$T_c$/Δp = -1.8 K/GPa). The rise of $J_{AF}$ interaction is attributed to the enhanced value of the single electron overlapping integral S. On the other hand, the applied pressure slightly affects bonding angles between magnetic ions mediated by the cyano-bridge and reduces the strength of magnetic coupling. Changes of the magnetization curve with pressure can be attributed to changes of magnetic anisotropy. The reduction of magnetization with pressure observed on $Cr^{2+}$-prussian blue analogues can be explained by pressure induced transition from $Cr^{2+}$ high spin state to $Cr^{2+}$ low spin state. All pressure induced changes are reversible.
Źródło:: Acta Physica Polonica A; 2008, 113, 1; 469-472
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 37.

Tytuł:: Effect of Pressure on Magnetic Properties of $TM_3[Cr(CN)_6]_2 \cdot nH_2O$ Nanoparticles
Autorzy:: Zentko, A.
Zentková, M.
Kavečanský, V.
Mihalik, M.
Mitróová, Z.
Arnold, Z.
Kamarád, J.
Cieslar, M.
Zeleňák, V.
Powiązania:: https://bibliotekanauki.pl/articles/1813843.pdf
Data publikacji:: 2008-01
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Cr
75.50.Ee
75.50.Gg
75.50.Xx
Opis:: Effect of pressure on magnetic properties of magnetic nanoparticles, based on Prussian blue analogues, were studied in pressures up to 1.2 GPa. The $Mn_3[Cr(CN)_6]_2 \cdot nH_2O$ and $Ni_3[Cr(CN)_6]_2 \cdot nH_2O$ nanoparticles were prepared by reverse micelle technique. Transmission electron microscopy images show nanoparticles with average diameter of about 3.5 nm embedded in an organic matrix. The characteristic X-ray peaks of nanoparticles are more diffused and broader. Systems of nanoparticles behave as systems of interacting magnetic particles. The Curie temperature $T_C$ is reduced from $T_C$ = 56 K for Ni-Prussian blue analogues to $T_C$ = 21 K for Ni-nanoparticles system and from $T_C$ = 65 K for Mn-Prussian blue analogues to $T_C$ = 38 K for Mn-nanoparticles system. One can explain this reduction of the Curie temperature and of the saturated magnetization $μ_s$ by dispersion of nanoparticles in an organic matrix i.e. by a dilution effect. Applied pressure leads to a remarkable increase in $T_C$ for system of Mn-nanoparticles (Δ$T_C$/Δp = +13 K/GPa) and to only slight decrease in $T_C$ for system of Ni-nanoparticles (Δ$T_C$/Δp = -3 K/GPa). The pressure effect follows behavior of the mother Prussian blue analogues under pressure. The increase in saturated magnetization, attributed to compression of the organic matrix, is very small.
Źródło:: Acta Physica Polonica A; 2008, 113, 1; 489-493
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 38.

Tytuł:: Temperature Influence on the Functional Properties of Inductive Components with Mn-Zn Ferrite Cores
Autorzy:: Jackiewicz, D.
Kachniarz, M.
Bieńkowski, A.
Powiązania:: https://bibliotekanauki.pl/articles/1030884.pdf
Data publikacji:: 2018-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 84.30.Jc
75.47.Lx
75.50.Gg
Opis:: The paper presents the results of investigation of the temperature influence on the inductance and power losses in ferrite cores. Such effect can significantly influence the utility parameters of electronic devices, particularly in precision equipment. For example slight parameter change in this type of components in measuring devices can cause significant changes in output parameters. It is also equally important for mobile devices where increase of losses can limit the duration of service. Special measurement system composed of hysteresis graph, cryostat and PC was utilized to perform the experiment. The cores used during the investigation had closed magnetic circuit. In order to perform measurements of magnetic properties of the material, two sets of windings (magnetizing and sensing) were made on each core. The cores were placed in a cryostat, which was used to set the temperature value within the range from -20 to +50°C. The magnetic properties were measured by the hysteresis graph, to assess the influence of the temperature on the functional parameters.
Źródło:: Acta Physica Polonica A; 2018, 133, 4; 1038-1040
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 39.

Tytuł:: Nickel/Zinc ratio and lanthanum substitution effect on structural and magnetic properties of nickel zinc ferrites
Autorzy:: Jančárik, V.
Šoka, M.
Ušáková, M.
Harťanský, R.
Powiązania:: https://bibliotekanauki.pl/articles/1053078.pdf
Data publikacji:: 2017-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.30.Cr
61.05.C-
Opis:: Improvement of NiZn ferrites properties by means on Ni/Zn content ratio modification and by partial substitution of Fe³⁺ ions by La³⁺ ions is presented. Ni_{x}Zn_{1-x}Fe₂O₄ and Ni_{x}Zn_{1-x}La_{0.02}Fe_{1.98}O₄ samples of small particles were prepared by self-propagated combustion method. X-ray spectroscopy was used for structural analysis, temperature dependence of magnetic susceptibility was used for evaluation of chemical and phase composition. Analysis showed that pure spinel structure without secondary phase caused by La ions for all values of Ni/Zn content was present. Noticeable growth of the magnetic susceptibility at room temperature was observed with rising of Zn²⁺ ions content.
Źródło:: Acta Physica Polonica A; 2017, 131, 4; 693-695
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 40.

Tytuł:: Crystal Structure and Magnetic Properties of Pyrrhotite-Type Compounds $Fe_{7-y}V_{y}S₈$
Autorzy:: Selezneva, N.
Ibrahim, P.
Toporova, N.
Sherokalova, E.
Baranov, N.
Powiązania:: https://bibliotekanauki.pl/articles/1397027.pdf
Data publikacji:: 2018-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 61.66.Fn
75.30.Kz
75.50.Gg
Opis:: The pyrrhotite-type compounds $Fe_{7-y}V_{y}S₈$ have been synthesized and studied by means of the X-ray diffraction and magnetization measurements in order to reveal how the substitution of V for Fe affects the crystal structure, phase transition and magnetic properties. The growth of the V content in $Fe_{7-y}V_{y}S₈$ results in changes of the crystal structure and leads to a sharp decrease in the resultant magnetization, non-monotonous change of the coercive field and reduction of the magnetic ordering temperature. Unlike ferrimagnetic ordering in pyrrhotite Fe₇S₈ the compound V₇S₈ is observed to exhibit a Pauli-paramagnetic behaviour.
Źródło:: Acta Physica Polonica A; 2018, 133, 3; 450-452
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 41.

Tytuł:: Effect of Tb/Gd Substitution on Crystal Structure and Exchange Interactions of $Gd_{1 - x}Tb_{x}Ni_3$ Intermetallic Compounds
Autorzy:: Chrobak, A.
Bajorek, A.
Chełkowska, G.
Powiązania:: https://bibliotekanauki.pl/articles/1427373.pdf
Data publikacji:: 2012-05
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.30.Et
71.20.Lp
Opis:: In the paper an influence of Tb/Gd substitution on crystal structure and exchange interactions of $Gd_{1 - x}Tb_{x}Ni_3$ (x = 0.0, 0.5, 0.8, 1.0) polycrystalline compounds have been studied. The crystal structure of all samples was checked at the room temperature by means of X-ray diffraction. Exchange integrals of $R-R (J_{RR}),$ $T-T (J_{TT})$ and $R-T (J_{RT})$ atoms were evaluated from M(T) magnetization curves (2-300 K, 2 T) based on the mean field theory calculation. As it was shown the samples examined are single phase and crystallize in the PuNi_3 (space group R-3m) type of crystal structure. The Tb/Gd substitution causes the decrease of lattice parameters as well as the volume of the unit cell. With increase of the x parameter the magnetic moment of Tb atoms increases from 6.94 $μ_{B}$ (x = 0.5) to 8.12 $μ_{B}$ (x = 1). The M(T) dependence of the examined compounds depends almost 8 times stronger on exchange interactions within the R-R site than the interactions between the two antiferromagnetically coupled magnetic sublattices R-T.
Źródło:: Acta Physica Polonica A; 2012, 121, 5-6; 1132-1135
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 42.

Tytuł:: Magnetism in TmCo₂
Autorzy:: Šebesta, J.
Prchal, J.
Valenta, J.
Kratochvílová, M.
Sechovský, V.
Powiązania:: https://bibliotekanauki.pl/articles/1385702.pdf
Data publikacji:: 2015-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.20.En
75.50.Gg
71.70.Gm
Opis:: Recently a new wave of interest in physics of RCo₂ compounds has been boosted by reports on unusual magnetic short range order configurations in the heavy rare-earth RCo₂ ferrimagnets in paramagnetic state. The newly observed phenomenon called parimagnetism consists in a short-range antiferromagnetic coupling between small ferromagnetic Co clusters and the nearest rare-earth moments. This paper is devoted to results of our experimental investigation of carefully prepared and characterized samples of TmCo₂, a compound on which controversial results can be found in literature. Detailed magnetization, AC susceptibility, specific heat and electrical resistivity measurements revealed two magnetic phase transitions at 4.6 and 3.6 K, respectively. The anomalies connected with the transitions are strongly dependent on magnetic field and hydrostatic pressure. The AC susceptibility anomaly connected with the onset of parimagnetism has been found at $T_{f}$=35 K. Contrary to other heavy rare-earth RCo₂ counterparts $T_{f}$ of TmCo₂ is entirely pressure independent.
Źródło:: Acta Physica Polonica A; 2015, 127, 2; 379-381
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 43.

Tytuł:: Mean-Field and Monte Carlo Study of a Mixed Ferro-Ferrimagnetic Ternary Alloy
Autorzy:: Dely, J.
Bobák, A.
Horváth, D.
Powiązania:: https://bibliotekanauki.pl/articles/1813809.pdf
Data publikacji:: 2008-01
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 05.10.Ln
75.10.Hk
75.50.Gg
Opis:: We present a study of the magnetic properties of a mixed ferro-ferrimag-netic ternary alloy of the type $AB_p C_{1-p}$ on a cubic lattice consisting of three different Ising spins $S_A$ =3/2, $S_B$ = 2, and $S_C$ = 5/2. We employ the mean-field approximation and Monte Carlo simulation to find the compensation temperatures of the system for selected values of the parameters in the model Hamiltonian. In particular, the relation between considered mixed ferro-ferrimagnetic model and magnetic properties of the ternary metal Prussian blue analog such as $(Fe_p^{II}Mn_{1-p}^{II})_1.5$ $[Cr^{III}(CN)_6] \cdot nH_2O$ is discussed.
Źródło:: Acta Physica Polonica A; 2008, 113, 1; 461-464
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 44.

Tytuł:: Magnetic Properties of Nano-Crystalline Barium Ferrite Synthesized by Different Synthesis Route
Autorzy:: Ovalioglu, H.
Sozeri, H.
Kabaer, M.
Kucuk, I.
Powiązania:: https://bibliotekanauki.pl/articles/1535266.pdf
Data publikacji:: 2010-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.50.Ss
75.50.Ww
61.72.U-
Opis:: We have synthesized $Ba_{1-x}La_{x}Fe_{12}O_{19}$ (0 ≤ x ≤ 0.4) and $BaFe_{12-y}Nd_{y}O_{19}$ (0 ≤ y ≤ 4) samples in ammonium nitrate melt and nitric acid. The effects of La and Nd doping on the microstructure and magnetic properties of $BaFe_{12}O_{19}$ were investigated. The highest coercive field was obtained for the sample having La content, x = 0.3.
Źródło:: Acta Physica Polonica A; 2010, 118, 5; 1020-1021
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 45.

Tytuł:: Influence of Substitution and Milling on Structural and Magnetic Properties of Selected $Sm(Ni_{1-x}Co_{x})₃$ Compounds
Autorzy:: Sikora, M.
Blachliński, D.
Ociepka, K.
Prusik, K.
Bajorek, A.
Chełkowska, G.
Powiązania:: https://bibliotekanauki.pl/articles/1397029.pdf
Data publikacji:: 2018-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Cr
75.30.Sg
75.50.Gg
75.50.Vv
Opis:: The influence of substitution of Co for Ni in $Sm(Ni_{1-x}Co_{x})₃$, where x=0.0, 0,1, 0.2, on the structural and magnetic properties has been investigated. Samples with x= 0.0 and 0.2 were subjected to grinding in a high energy ball mill. The presence of a PuNi₃ type of crystal phase was evidenced for bulk crystalline and powders specimens. With an increase in the cobalt content, an increase at T_{c} was observed. From the magnetic isotherms, the magnetic entropy changes were determined both for solid and powdered samples. It has been shown that the value of the magnetic entropy change at T_c is doubled for the bulk sample with x= 0.2 but it has decreased significantly for all powdered samples.
Źródło:: Acta Physica Polonica A; 2018, 133, 3; 486-488
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 46.

Tytuł:: Effect of Manganese on Magnetic and Electrical Properties of the RMn$\text{}_{x}$T$\text{}_{12-x}$ Alloys
Autorzy:: Suski, W.
Wochowski, K.
Mydlarz, T.
Belan, B.
Powiązania:: https://bibliotekanauki.pl/articles/2014385.pdf
Data publikacji:: 2000-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.20.-g
75.20.En
75.50.Ee
Opis:: The magnetic and electrical properties of the tetragonal, ThMn$\text{}_{12}$-type RMn$\text{}_{x}$T$\text{}_{12-x}$ alloys (R = Y, Ce, Pr, Nd, Sm and T = Fe, Co, Ni) were studied in broad temperature and magnetic field ranges to elucidate an influence of manganese on the magnetic ordering in these materials. Magnetic properties were examined at T=1.7-300K in magnetic field up to 14T, whereas the electrical properties were examined at T=4.2-300K, on the polycrystalline samples. Majority of the samples exhibit ferro- or ferrimagnetic properties. Some samples containing larger concentration of Mn are paramagnetic in the whole temperature range. The electrical resistivity of these alloys shows metallic character.
Źródło:: Acta Physica Polonica A; 2000, 98, 5; 505-511
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 47.

Tytuł:: Influence of Microstructure Evolution on the Coercive Forces in Low Silicon Non-Oriented Steels
Autorzy:: Petryshynets, I.
Kovac, F.
Stoyka, V.
Boruta, J.
Powiązania:: https://bibliotekanauki.pl/articles/1535233.pdf
Data publikacji:: 2010-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.20.En
74.25.Ha
75.50.Bb
75.50.Gg
Opis:: The magnetic properties and their dependence on the peculiarity of microstructure in low silicon non-oriented electrotechnical steels were studied in the present work. The estimation of dc magnetic properties of electrical steels was carried out by measurements of coercive forces. It was shown that the coercive force change in silicon steels is dependent on change of average grain size, crystallographic texture and homogeneity of microstructure of the materials. It was revealed that the steels possessing columnar or huge grained microstructure had the lowest measured values of coercive forces. The materials with such microstructure are characterized by a domination of (100) 〈0vw〉 crystallographic orientation.
Źródło:: Acta Physica Polonica A; 2010, 118, 5; 1013-1014
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 48.

Tytuł:: Tracking the Evolution of Abnormal Grain Growth in Grain-Oriented Electrical Steels by Coercivity Measurements
Autorzy:: Stoyka, V.
Kovac, F.
Petryshynets, I.
Schindler, I.
Powiązania:: https://bibliotekanauki.pl/articles/1535242.pdf
Data publikacji:: 2010-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 74.25.Ha
75.20.En
75.50.Bb
75.50.Gg
Opis:: The measurements of coercivity were utilised to investigate the main evolution stages of abnormal grain growth in grain-oriented electrical steels. The investigated grain-oriented steels were taken from industrial line after final cold rolling. The steels were subjected to short time annealing at elevated temperatures with high heating rates. The coercivity measurements carried out within the present work were confronted with microstructure and texture analysis in order to show the direct dependence of the measured coercivities on metallurgical characteristics of the investigated steel. It is shown that the coercivity measurements technique could capture main microstructural changes taking place in recrystallization.
Źródło:: Acta Physica Polonica A; 2010, 118, 5; 1015-1017
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 49.

Tytuł:: Rhombohedral Distortion in Fe$\text{}_{3-y}$Zn$\text{}_{y}$O$\text{}_{4}$ at Verwey Transition
Autorzy:: Kozłowski, A.
Kąkol, Z.
Zalecki, R.
Knight, K.
Honig, J. M.
Powiązania:: https://bibliotekanauki.pl/articles/1955841.pdf
Data publikacji:: 1997-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
64.70.Kb
61.12.-q
Opis:: The time-of-flight neutron diffraction data were collected for two Fe$\text{}_{3-y}$Zn$\text{}_{y}$O$\text{}_{4}$ powder samples showing different order of the Verwey transition: y=0.0072 - first order, y=0.0249 - second order. Measurements were performed on spallation neutron source in ISIS Rutherford Appleton Laboratory. At low temperatures (below Verwey transition temperature T$\text{}_{V}$) clear splitting of certain reflections characteristic of rhombohedral distortion was observed for both samples. We found that this distortion is much bigger for the sample exhibiting first-order than for the sample showing second-order transition.
Źródło:: Acta Physica Polonica A; 1997, 91, 2; 443-446
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 50.

Tytuł:: The influence of NiZnFe₂O₄ content on magnetic properties of supermalloy type material
Autorzy:: Ďáková, L'.
Füzer, J.
Dobák, S.
Kollár, P.
Fáberová, M.
Strečková, M.
Bureš, R.
Hadraba, H.
Powiązania:: https://bibliotekanauki.pl/articles/1053020.pdf
Data publikacji:: 2017-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 07.55.-w
75.60.-d
75.50.Bb
75.50.Gg
Opis:: Soft magnetic composites represent a remarkable kind of materials with wide variety of use. Magnetic properties are dependent on the materials composition and also on the method of preparation. Ni-Fe-Mo alloys (supermalloy) have high complex permeability and low eddy current losses. Soft magnetic NiZnFe₂O₄ ferrites have low coercivity and intermediate saturation magnetization. The Ni_{80}Fe_{14.7}Mo_{4.5}Mn_{0.5}Si_{0.3} (wt%) powder sample was prepared by mechanical alloying of the chemical elements for 24 h. Ni_{0.3}Zn_{0.7}Fe₂O₄ ferrite is commercially available by Sigma Aldrich. Both powders were mixed at selected ratio and uniaxially compacted at 800 MPa. In this paper, we report the experimental observations of the effects of Ni_{0.3}Zn_{0.7}Fe₂O₄ content on the electromagnetic properties of NiFeMoMnSi/Ni_{0.3}Zn_{0.7}Fe₂O₄. The samples contained 5, 10, and 15% of Ni_{0.3}Zn_{0.7}Fe₂O₄ ferrite and were sintered for 30 min at 800°C. An addition of Ni_{0.3}Zn_{0.7}Fe₂O₄ ferrite caused decrease of complex permeability and increase coercivity of the samples. The 5% of Ni_{0.3}Zn_{0.7}Fe₂O₄ sample exhibits the highest value of the real part of complex permeability (48 at 1 kHz). The 10% of Ni_{0.3}Zn_{0.7}Fe₂O₄ sample showed the lowest total magnetic losses.
Źródło:: Acta Physica Polonica A; 2017, 131, 4; 813-815
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 51.

Tytuł:: Electronic and magnetic properties of Ca-doped Mn-ferrite
Autorzy:: Ustundağ, M.
Aslan, M.
Powiązania:: https://bibliotekanauki.pl/articles/1068186.pdf
Data publikacji:: 2016-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 71.15.Mb
71.20.-b
75.50.Gg
Opis:: Spinel ferrite structures have vast applications, from microwave to radio frequencies. In order to acquire new electronic and optical behavior, divalent cations can be added to normal spinel ferrite structure. This way it is possible to facilitate its usage in material and science technology. In this work we have analyzed the impact of Ca addition to normal spinel manganese ferrite on electronic and magnetic properties by the first-principles calculations. For the exchange-correlation functional, Wu-Cohen, generalized gradient approximation method was used for electron-electron interactions. The calculation of electronic band structures is based on full potential linear augmented plane wave method. The calculated density of states shows that the addition of Ca ions has a significant impacts on the electronic and magnetic structure.
Źródło:: Acta Physica Polonica A; 2016, 130, 1; 362-364
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 52.

Tytuł:: Magnetic Properties of 4f-3d Intermetallics Studied by $\text{}^{161}$Dy and $\text{}^{57}$Fe Mössbauer Effect
Autorzy:: Pszczoła, J.
Powiązania:: https://bibliotekanauki.pl/articles/2011002.pdf
Data publikacji:: 1999-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 76.80.+y
75.50.Gg
71.20.Lp
Opis:: Applications of the Mössbauer effect at the $\text{}^{161}$Dy and $\text{}^{57}$Fe nuclei to study heavy rare earth - transition metal compounds are presented. Magnetic hyperfine fields at dysprosium and iron nuclei observed in the Dy$\text{}_{u}$(M-M)$\text{}_{v}$ intermetallics (u/v=2/17, 6/23, 1/3, and 1/2; M-M = Mn-Fe, Fe-Co, and Co-Ni), magnetic moments and magnetic ordering temperatures are discussed. The magnetic hyperfine field at iron nuclei and the field at dysprosium nuclei treated as functions of a number of 3d electrons form two different systems of the Slater-Pauling curves. The magnetic ordering temperatures treated as functions of the number of 3d electrons also form the u/v system of curves. Considering the magnetic data and the magnetic hyperfine fields it can be concluded that intermetallics can be treated as three-subsystem ferrimagnets. Consequently, a coexistence between the 4f, 5d, and 3d magnetism in the rare earth - transition metal compounds can be qualitatively explained.
Źródło:: Acta Physica Polonica A; 1999, 96, 1; 113-122
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 53.

Tytuł:: Structural and Magnetic Features of $Mn_{1-x}Zn_xFe_2O_4$ Nanoparticles
Autorzy:: Mendoza, A.
Prado, J.
Almanza, O.
Powiązania:: https://bibliotekanauki.pl/articles/1431791.pdf
Data publikacji:: 2012-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.75.Fk
75.30.Gw
75.60.Ch
75.50.Gg
Opis:: This paper reports on the magnetic properties of $Mn_{1-x}Zn_x$-ferrite nanoparticles. Different x compositions of the magnetic material have been considered. Field- and temperature-dependent magnetization curves and electron paramagnetic resonance (EPR) at different temperatures were used to reveal the magnetic properties of the samples. For x=0.5, the EPR spectra consist of a single resonance signal, strongly symmetrical, with g = 3.25 close to 2073 G, and an asymmetric line corresponding to g = 4.4 for x = 0. The asymmetry is attributed to a random distribution of the anisotropy in the system, with perpendicular and parallel modes, giving information about the effective anisotropy of the system. For high concentrations, the resonant field shifts to 2875 G. Magnetization measurements as function of temperature at 60 Oe according to the standard zero field cooling (ZFC) and field cooling (FC) procedures are reported. The behavior of field cooling magnetization (MFC) at low temperatures evidences the presence of strong interparticles interactions.
Źródło:: Acta Physica Polonica A; 2012, 121, 4; 950-953
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 54.

Tytuł:: Microstructural and magnetic characteristics of divalent Zn, Cu and Co-doped Ni ferrites
Autorzy:: Šoka, M.
Dosoudil, R.
Ušáková, M.
Powiązania:: https://bibliotekanauki.pl/articles/1054856.pdf
Data publikacji:: 2017-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
76.50.+g
75.78.-n
74.62.Bf
Opis:: Divalent zinc, copper and cobalt doped nickel ferrites with the chemical formula Ni_{1-x-y-z}Zn_{x}Cu_{y}Co_{z}Fe₂O₄ where x values ranging from 0.4 to 0.6, y=0.1, z=0.01 and 0.02 have been synthesized by conventional ceramic method. The effect of Zn²⁺, Cu²⁺ and Co²⁺ ions substitution on the selected microstructural and magnetic characteristics have been investigated to examine the utility of prepared ferrite materials for high-frequency applications. X-ray diffraction measurements confirmed the single-phase spinel cubic structure in all the samples and modifications in lattice parameter according to the ionic radii size of doped ions. The net magnetic moment, given by the differences between the magnetic moments of A and B sublattice, increased with raising substitution of Ni²⁺ ions. The measured frequency dispersion of complex permeability was discussed in terms of the changes in chemical composition, microstructure and the associated processes of resonance and/or relaxation due to domain wall movements and damping of spin rotations contributing to the fall of permeability and rise of magnetic losses.
Źródło:: Acta Physica Polonica A; 2017, 131, 4; 690-692
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 55.

Tytuł:: Peculiarities of the Electronic Properties of the κ-Phase Structures (BEDT-TTF)$\text{}_{2}$Cu(N(CN)$\text{}_{2}$)X with X=Cl, Br, I
Autorzy:: Andres, K.
Posselt, H.
Kushch, N.
Kund, M.
Biberacher, W.
Saito, G.
Powiązania:: https://bibliotekanauki.pl/articles/1933335.pdf
Data publikacji:: 1995-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 72.80.Le
75.50.Gg
75.50.Ee
74.70.Kn
Opis:: The structure of the title compounds is similar to other κ-phase structures with respect to the checkerboard-like arrangement of the ET dimers (ET = BEDT-TTF) in the conducting planes, but different by the tilt alternation of these dimers in successive planes. The resulting inequivalence of these planes tends to destabilize the metallic state which becomes extremely sensitive to changes in the S-S overlaps of neighbouring ET molecules. Such changes may result from anion substitution, lattice expansion, or also from ordering effects of the ethylene end groups of the ET molecules. They lead to quite different electronic properties of the three isostructural compounds. We focus especially on the strongly pressure-dependent properties of the Cl-compound, where a coexistence of magnetically ordered and superconducting states with rather spectacular superconducting reentrance effects is observed.
Źródło:: Acta Physica Polonica A; 1995, 87, 4-5; 761-766
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 56.

Tytuł:: Effect of Vanadium Substitution of Cobalt in $NdCo_2Si_2$
Autorzy:: Chowdhury, R.
Dhara, S.
Bandyopadhyay, B.
Powiązania:: https://bibliotekanauki.pl/articles/1402070.pdf
Data publikacji:: 2015-10
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 71.20.Lp
75.50.Gg
75.50.Ee
75.50.Cc
75.50.Dd
Opis:: In NdCo₂Si₂, partial substitution of Co by V having a larger atomic radius results in negative pressure affecting the magnetic properties of the compound. The samples $Nd(Co_{1-x}V_{x})_Si_2$ (x=0, 0.20, 0.35) have been prepared and characterized using X-ray diffraction. The parent compound NdCo₂Si₂ is antiferromagnetic with $T_{N}$ of 34 K whereas the temperature dependence of inverse susceptibility in the doped samples show ferrimagnetic behaviour below 45 K. From the magnetic field dependence of magnetization and the coercive fields obtained from hysteresis loops, the doped samples exhibit ferromagnetism below ≈ 20 K. The specific heat studies compare the magnetic transitions in the parent and doped samples. $Nd(Co_{0.65}V_{0.35})_2Si_2$ shows a magnetoresistance of 15% at 4 K.
Źródło:: Acta Physica Polonica A; 2015, 128, 4; 530-532
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 57.

Tytuł:: Effect of Nd³⁺ doping on magnetic and dielectric properties of SrFe₁₂O₁₉ hexaferrite synthesized by coprecipitation method
Autorzy:: Hilczer, A.
Pasińska, K.
Markiewicz, E.
Pietraszko, A.
Andrzejewski, B.
Powiązania:: https://bibliotekanauki.pl/articles/1047614.pdf
Data publikacji:: 2018-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.60.Ej
75.75.+a
81.20.Fw
Opis:: Magnetic and dielectric properties of hexagonal ferrites important for applications in microwave absorbers are strongly determined by the processing conditions. We studied dielectric and magnetic response of Sr_{1-x}Nd_{x}Fe₁₂O₁₉ (x=0, 0.03, 0.05, 0.07, 0.09) solid solutions obtained by coprecipitation method. The structure of the samples was controlled by X-ray diffraction and scanning electron microscope images revealed that the powder is a mixture of small nanograins and crystallites of 500 nm-1 μm in size. Nd³⁺ doping was found to result in an increase in the coercive field which we would like to relate to the domain wall pinning. The doping-induced changes are monotonous with x up to 0.07. The observed dispersion of permittivity was found to be correlated with the frequency behaviour of electric conductivity of the samples.
Źródło:: Acta Physica Polonica A; 2018, 133, 3; 669-672
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 58.

Tytuł:: Preparation and Investigations of $Ni_{0.2}Zn_{0.8}Fe_2O_4$ Ferrite Nanofiber Membranes by Needleless Electrospinning Method
Autorzy:: Streckova, M.
Mudra, E.
Sebek, M.
Sopcak, T.
Dusza, J.
Kovac, J.
Powiązania:: https://bibliotekanauki.pl/articles/1398266.pdf
Data publikacji:: 2017-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.75.Cd
75.50.Gg
81.07.-b
75.47.Lx
Opis:: The preparation of $Ni_{0.2}Zn_{0.8}Fe_2O_4$ nanofiber membranes by simple and versatile needleless electrospinning technique is presented. The single phase of spinel ferrite membrane was obtained after conventional thermal treatment of polyvinyl alcohol (PVA)/metal nitrate precursors at 800°C for 4 h in air. The formation of single-phase fibers was characterized using differential scanning calorimetry accompanied with thermogravimetric analysis. The surface morphology, microstructure and crystal structure were investigated by scanning electron microscopy, X-ray diffraction and transmission electron microscopy. The magnetic properties of the fibrous samples measured in the temperature range from 2 to 300 K verify a soft magnetic behavior, which is quite typical for ferrimagnetic spinel-type ferrites.
Źródło:: Acta Physica Polonica A; 2017, 131, 4; 729-731
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 59.

Tytuł:: Phase Transitions Induced in HoCo$\text{}_{3}$Ni$\text{}_{2}$ Single Crystals
Autorzy:: Zawadzki, J.
Ballou, R.
Gorges, B.
Szymczak, R.
Powiązania:: https://bibliotekanauki.pl/articles/1928269.pdf
Data publikacji:: 1993-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Gw
75.30.Kz
75.50.Gg
75.60.Ej
Opis:: The magnetic studies of temperature and field induced phase transitions were performed on single crystals of HoCo$\text{}_{3}$Ni$\text{}_{2}$ compound. The rotational-type spin reorientation was found between T$\text{}_{SR1}$ = 160 K and T$\text{}_{SR2}$ = 200 K. In the vicinity of T$\text{}_{SR1}$ two different field induced transitions were observed: the first order moment reorientation type transition in the basal plane and the spin reorientation from the easy plane to the c-axis with simultaneous increase in spontaneous magnetization. The intersublattice molecular field coefficient as well as the magnetization anisotropy of Ho sublattice were determined. The observed magnetic behaviour was analysed within the framework of the spin-reorientation model, taking into account the change of the intrinsic states of rare-earth ions caused by their huge anisotropy energy. The thermal variation of the anisotropy constants of the studied compound is also presented.
Źródło:: Acta Physica Polonica A; 1993, 83, 2; 209-218
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 60.

Tytuł:: Study of Magnetic and Structural Properties of Non-Stoichiometric NiZn Ferrites Prepared by Wet Method
Autorzy:: Grusková, A.
Sláma, J.
Ušáková, M.
Šoka, M.
Dosoudil, R.
Degmová, J.
Powiązania:: https://bibliotekanauki.pl/articles/1507192.pdf
Data publikacji:: 2010-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.30.Cr
75.30.-m
82.80.Ej
Opis:: An iron-deficient $(Ni_{0.33}Zn_{0.67})_{1 + x}Fe_{2 - x}O_4$ and stoichiometric $Ni_{0.45}Zn_{0.55}Fe_2O_4$ prepared by a wet method were studied using the Mössbauer spectroscopy and thermomagnetic measurements. For the iron-deficient sample the $T_{C}$ is twice as large and the temperature coefficient of initial permeability is two orders of magnitude lower in comparison with the stoichiometric samples. The results are supplemented by the frequency dependence of the complex permeability.
Źródło:: Acta Physica Polonica A; 2010, 118, 5; 780-781
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 61.

Tytuł:: Magnetic Properties of Yttrium-Substituted NiZn Ferrites
Autorzy:: Jančárik, V.
Ušák, E.
Šoka, M.
Ušáková, M.
Powiązania:: https://bibliotekanauki.pl/articles/1367108.pdf
Data publikacji:: 2014-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.30.Cr
75.60.-d
74.62.Dh
Opis:: Polycrystalline NiZn ferrite doped with a small amount of $Y^{3+}$ ions and having the composition of $Ni_{0.42}Zn_{0.58}Y_{x}Fe_{2-x}O_{4}$, where x=0.00, 0.01, 0.02, 0.04, 0.06, 0.08 and 0.10, was analyzed. Specimens were prepared by the ceramic method. Thermo-magnetic analysis and evaluation of hysteresis loops parameters were chosen as main examination methods in this study. Various parameters, such as Curie temperature $T_{C}$, coercive field $H_{c}$, remanent magnetic flux density $B_{r}$, hysteresis loop area and amplitude/initial permeability were studied at low frequencies.
Źródło:: Acta Physica Polonica A; 2014, 126, 1; 90-91
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 62.

Tytuł:: Investigation of Magnetoelastic Properties of $Ni_{0.36}Zn_{0.64}Fe_2O_4$ Ferrite Material under Low Magnetizing Fields Corresponding to Rayleigh Region
Autorzy:: Kachniarz, M.
Bieńkowski, A.
Szewczyk, R.
Powiązania:: https://bibliotekanauki.pl/articles/1398307.pdf
Data publikacji:: 2017-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.30.-m
07.55.-w
75.80.+q
Opis:: The following paper presents original results of study on the magnetoelastic properties of Ni-Zn (nickel-zinc) ferrite material under low magnetizing fields, corresponding to the so-called Rayleigh region. The investigated $Ni_{0.36}Zn_{0.64}Fe_2O_4$ material was formed into frame-shape sample allowing to obtain uniform stress distribution. Special digitally controlled measurement system was utilized to perform investigation. Obtained results are presented in the paper. On the basis of them mathematical description of magnetoelastic effect in investigated material was developed as an extend of the Rayleigh model of magnetic hysteresis. Comparison of the experimental and modeling results indicates that the developed model is correct.
Źródło:: Acta Physica Polonica A; 2017, 131, 4; 1066-1068
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 63.

Tytuł:: Structural and Magnetic Properties of Dy(Fe,V,Si)$\text{}_{12}$ Compounds
Autorzy:: Drzazga, Z.
Winiarska, A.
Chrobak, A.
Kaczorowski, D.
Powiązania:: https://bibliotekanauki.pl/articles/1964633.pdf
Data publikacji:: 1997-08
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.Gw
75.50.Gg
75.30.Cr
61.10.-i
Opis:: An influence of Si on the structural and magnetic properties of Dy(Fe,V,Si)$\text{}_{12}$ compounds is studied. X-ray diffraction shows that these materials crystallise in the tetragonal ThMn$\text{}_{12}$-type structure. An increase in the saturation magnetization, the Curie temperatures and magnetocrystalline anisotropy in the Si substitutional systems is observed when compared with DyFe$\text{}_{12-x}$V$\text{}_{x}$. The magnetic properties depend on the preferential site occupation and concentration of Si and V atoms in these compounds.
Źródło:: Acta Physica Polonica A; 1997, 92, 2; 335-338
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 64.

Tytuł:: Preparation and Magnetic Characteristics of $Co_{1-δ}Zn_{δ}Fe_2O_4$ Ferrite Nanopowders
Autorzy:: Kubisztal, M.
Herok, I.
Karolus, M.
Prusik, K.
Haneczok, G.
Powiązania:: https://bibliotekanauki.pl/articles/1398315.pdf
Data publikacji:: 2017-05
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.47.Lx
75.50.Gg
75.50.Tt
75.75.-c
75.75.Cd
Opis:: In the present paper the $Co_{1-δ}Zn_{δ}Fe_2O_4$ (0 ≤ δ ≤ 1) ferrite nanopowders with a spinel type structure were synthesized using a chemical co-precipitation technique with constant flow rate $ν _{FR}$=120 cm³/min at three different reaction temperatures i.e. $T_r$ =50°C, 70°C and 90°C. Magnetic and structural characteristics of the obtained materials were investigated by means of X-ray diffraction method, transmission electron microscopy and vibrating sample magnetometer. In the course of studies hysteresis loops M(μ₀H) and the relations of magnetization $M_{7T}$ (determined at $\text{}_{μ0}H $=7 T), squareness ratio S and the Néel temperature $T_{N}$ versus Zn content were determined and discussed in detail. It was shown that for δ<0.6 the increase in reaction temperature $T_r$ results in a significant increase of the measured magnetic characteristics. In particular, in the case of $Co_{0.8}Zn_{0.2}Fe_2O_4$ ferrite nanopowder magnetization $M_{7T}$ reaches maximal value of about 80 emu/g.
Źródło:: Acta Physica Polonica A; 2017, 131, 5; 1236-1239
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 65.

Tytuł:: Magnetic Topological Structures in Multiferroics
Autorzy:: Gareeva, Z.
Zvezdin, K.
Popkov, A.
Zvezdin, A.
Powiązania:: https://bibliotekanauki.pl/articles/1030690.pdf
Data publikacji:: 2018-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.85.+t
75.50.Ee
75.30.Fv
75.50.Gg
75.60.Ch
Opis:: In this article we focus on impact of micromagnetic structures on magnetoelectricity of multiferroics. We discuss physical mechanisms of magnetoelectric coupling considering domain walls and spin cycloids. We review the progress on multiferroic materials focusing on high temperature multiferroic: rare earth iron garnet and bismuth ferrite. We argue that topological structures play a pivotal role in multiferoics and show that electric control of magnetism can be carried out via spin spirals and domain walls. Magnetic domain walls produce ferroelectricity in rare earth iron garnets; transformations of spin cycloids release magnetoelectricity in bismuth ferrite. Ferroic orders couple via magnetic inhomogeneities, which shed new light on fundamental physics and applications.
Źródło:: Acta Physica Polonica A; 2018, 133, 3; 380-383
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 66.

Tytuł:: Analysis of Magnetic Ground State in Thulium Iron Garnets
Autorzy:: Koper, A.
Lehmann-Szweykowska, A.
Wigen, P. E.
Bornfreund, R. E.
Powiązania:: https://bibliotekanauki.pl/articles/1964707.pdf
Data publikacji:: 1997-08
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Lk
75.50.Gg
75.50.-y
75.40.Μg
75.10.Hk
Opis:: Magnetic phase diagrams of thulium iron garnets at Τ = 0 K are obtained by means of the so-called Monte Carlo relaxation method. The diagrams are given in terms of the respective strength of the superexchange couplings. There are five different phases and one spin-flop line on the diagram obtained. Two of these phases are of a semi-spin glass type.
Źródło:: Acta Physica Polonica A; 1997, 92, 2; 391-394
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 67.

Tytuł:: Distribution of Zn in Magnetoelectric Y-Type Hexaferrite
Autorzy:: Kouřil, K.
Chlan, V.
Štěpánková, H.
Telfah, A.
Novák, P.
Knížek, K.
Hiraoka, Y.
Kimura, T.
Powiązania:: https://bibliotekanauki.pl/articles/1506927.pdf
Data publikacji:: 2010-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 61.05.Qr
75.85.+t
75.50.Gg
31.15.E-
Opis:: We employ $\text{}^{67}Zn$ NMR to study distribution of $Zn^{2+}$ in cationic sites of magnetoelectric Y-type hexaferrite single crystal, $Ba_{0.5} Sr_{1.5} Zn_2 Fe_{12} O_{22}$. The experimental data are interpreted by comparison with NMR spectra simulated from ab initio calculated hyperfine parameters.
Źródło:: Acta Physica Polonica A; 2010, 118, 5; 732-733
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 68.

Tytuł:: Study of Y-type Hexaferrite by Means of $\text{}^{57}Fe$ NMR and Electronic Structure Calculations
Autorzy:: Chlan, V.
Kouřil, K.
Štěpánková, H.
Řezníček, R.
Englich, J.
Powiązania:: https://bibliotekanauki.pl/articles/1378196.pdf
Data publikacji:: 2014-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 61.05.Qr
75.85.+t
75.50.Gg
31.15.E-
Opis:: The electron structure and site preferences of Zn and Fe cations in Y hexaferrite system were calculated. The hyperfine magnetic fields on $\text{}^{57}Fe$ nuclei were determined using WIEN2k and corrections for hyperfine contact interaction. The calculated fields were compared to $\text{}^{57}Fe$ nuclear magnetic resonance (NMR) experiment in $Ba_2Zn_2Fe_{12}O_{22}$ single crystal with an aim of interpretation of experimental NMR spectrum.
Źródło:: Acta Physica Polonica A; 2014, 126, 1; 42-43
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 69.

Tytuł:: Observation of Anisotropic Exchange in a Spin Ladder by ESR
Autorzy:: Čižmár, E.
Ozerov, M.
Krämer, K.
Rüegg, Ch.
Zvyagin, S.
Powiązania:: https://bibliotekanauki.pl/articles/1368577.pdf
Data publikacji:: 2014-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 76.30.-v
74.25.Ha
75.50.Gg
75.30.Gw
Opis:: We report on high resolution X-band electron spin resonance (ESR) spectroscopy studies of the spin-ladder material $(C_{5}H_{12}N)_{2}CuBr_{4}$. Our experiments provide a direct evidence for the presence of anisotropy in $(C_{5}H_{12}N)_{2}CuBr_{4}$ in contrast to a fully isotropic spin-ladder model employed for this system previously. Low-temperature angular dependence of ESR transitions is analyzed employing a simple spin-1/2 dimer model with the symmetric anisotropic exchange interaction.
Źródło:: Acta Physica Polonica A; 2014, 126, 1; 238-239
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 70.

Tytuł:: Second-Harmonic Generation Studies of Inhomogeneous Magnetization Distributions in Thin Garnet Film
Autorzy:: Bonda, A.
Uba, S.
Uba, L.
Powiązania:: https://bibliotekanauki.pl/articles/1386869.pdf
Data publikacji:: 2015-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 78.20.Ls
42.65.Ky
75.50.Gg
75.70.-i
Opis:: The magnetization processes can be effectively studied using magnetization-induced second-harmonic generation effect (MSHG). The aim of the current work is the investigation of inhomogeneous magnetization distributions induced in the surface area of the garnet film by ion implantation. The studies were performed on magnetic garnet film of (111) symmetry, implanted with H⁺₂ ions of 1.5 × 10¹⁶ cm¯² dose and 60 keV energy. The measurements of MSHG effect were performed as a function of the sample rotation angle and the amplitude of external magnetic field. The observed MSHG intensity hystereses were subjected to a decomposition procedure into contributions having different magnetic field dependences. The contributions originating from the implanted and unimplanted parts of the film volume of different magnetic ordering were analyzed and discussed.
Źródło:: Acta Physica Polonica A; 2015, 127, 2; 511-513
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 71.

Tytuł:: Magnetic Properties of the Rapidly Solidified Bulk Alloy: $Fe_{61}Co_{10}B_{20}Y_{8-x}W_{y}Pt_{x}$ (where: x=1,2; y=0,1)
Autorzy:: Pietrusiewicz, P.
Powiązania:: https://bibliotekanauki.pl/articles/1397021.pdf
Data publikacji:: 2018-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 61.43.Dq
75.50.Gg
75.50.Tt
75.30.Kz
75.60.Ej
Opis:: In the literature, research into rapidly cooled Pt-based alloys usually features samples that are produced in the form of thin ribbons. This work presents the effect of the addition of a small quantity of W and Pt on the magnetic properties of massive two-phase alloys, the samples being produced in the form of plates with a thickness of 0.5 mm. Both amorphous and crystalline phases were observed in the alloys, the phase proportions depending on the composition of the alloy. Generally, it is assumed that alloys with added Pt are characterised by a relatively high saturation magnetization and magnetocrystalline anisotropy, which is mainly influenced by the presence of the crystalline phases: FePt and Fe₃Pt. For the investigated alloys, it was noted that the gradual substitution of W and Pt in place of Y within the alloy $Fe₆₁Co₁₀B₂₀Y_{8-x}W_{y}Pt_{x}$ increased the value of saturation magnetization $(μ₀M_{s})$ and reduced the coercive field $(H_{c})$. On the basis of XRD pattern analysis it was found that, within the sample with the highest concentration of Pt, there are crystallites of the smallest size and the proportion of the α-Fe crystalline phase is much greater than for the other studied samples.
Źródło:: Acta Physica Polonica A; 2018, 133, 3; 666-668
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 72.

Tytuł:: Effect of Filler Mixture Ratio on Permeability of Multicomponent Soft Magnetic Composites
Autorzy:: Dosoudil, R.
Ušáková, M.
Grusková, A.
Sláma, J.
Powiązania:: https://bibliotekanauki.pl/articles/1202349.pdf
Data publikacji:: 2014-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.50.Bb
76.50.+g
75.78.-n
72.80.Tm
Opis:: Composites with hybrid LiZnTi ferrite/FeSiAl alloy filler and PVC polymer matrix were synthesized by thermal pressing process. The influence of the mixture ratio of hybrid filler on the frequency dispersion of complex permeability of the composites has been studied. The dispersion of permeability varied from resonance type to relaxation one with the configuration change from LiZnTi/PVC composite to FeSiAl/PVC one and was mainly due to the magnetic resonance phenomena such as domain wall and spin precession resonance and due to the eddy current effect.
Źródło:: Acta Physica Polonica A; 2014, 126, 1; 404-405
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 73.

Tytuł:: Monte Carlo Study of Selective Magnetic Dilution in Spinel Structure
Autorzy:: Pytlik, L.
Powiązania:: https://bibliotekanauki.pl/articles/2013733.pdf
Data publikacji:: 2000-05
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.10.Hk
75.10.Nr
75.40.Mg
75.50.Lk
75.50.Gg
Opis:: In the present work results of a Monte Carlo study of magnetic ordering and percolation tresholds in selectively diluted spinel structure are discussed. Classical spin model with the Heisenberg type interactions was used with additional cubic anisotropy terms. Three types of selective dilution were studied: separate dilutions of A and B sublattices and a homogeneous dilution of both sublattices. The results are compared for various degrees of magnetic competition between first and second neighbours interactions.
Źródło:: Acta Physica Polonica A; 2000, 97, 5; 913-916
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 74.

Tytuł:: Magnetic properties of Co-Fe-Si-B microwires
Autorzy:: Kwapuliński, P.
Gieraltowski, J.
Dolabdjian, C.
Stokłosa, Z.
Haneczok, G.
Powiązania:: https://bibliotekanauki.pl/articles/1055108.pdf
Data publikacji:: 2017-05
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 72.15.Gd
75.30.Gw
75.50.Gg
75.50.Kj
75.90.+w
Opis:: In the paper the magneto-impedance effect in the Co_{68.15}Fe_{4.35}Si_{12.55}B_{15} microwire with diameter of about 100 μ m is carefully studied. The measurements in close contact and contactless geometry were carried out in the static field ranging from 0 to 6 kA/m and frequencies of the alternating field from 20 Hz to 2 MHz. It is shown that the examined microwire shows high anisotropy of soft magnetic properties i.e. the circumferential permeability is at least 7 times higher than the longitudinal one. Moreover, the microwire can be used as highly sensitive magneto-impedance sensor working in contactless geometry especially at fields below 200 A/m.
Źródło:: Acta Physica Polonica A; 2017, 131, 5; 1256-1259
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 75.

Tytuł:: The Magnetic Properties of $GaFeO_3$ by Neutron Diffraction and Mössbauer Spectroscopy
Autorzy:: Rećko, K.
Szymański, K.
Dobrzyński, L.
Waliszewski, J.
Powiązania:: https://bibliotekanauki.pl/articles/1419611.pdf
Data publikacji:: 2012-08
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 61.05.fm
61.05.Qr
75.50.Gg
75.50.Ee
75.85.+t
Opis:: The multiferroic $GaFeO_3$ synthesized by a sol-gel method and conventional solid state reaction show remarkably different magnetic transition temperatures. Both samples have orthorhombic crystal structure $Pc2_1n$. Results of a new analysis of neutron diffraction and Mössbauer data are presented. Full agreement between parameters was achieved using the Mössbauer data as the constraints in the refinement of neutron diffraction data at low and at high temperature. Magnetic moments are reported.
Źródło:: Acta Physica Polonica A; 2012, 122, 2; 396-399
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 76.

Tytuł:: Nuclear Magnetic Resonance in Hexaferrite/Maghemite Composite Nanoparticles
Autorzy:: Křišťan, P.
Hondlík, O.
Štěpánková, H.
Chlan, V.
Kouřil, K.
Řezníček, R.
Pollert, E.
Veverka, P.
Powiązania:: https://bibliotekanauki.pl/articles/1386884.pdf
Data publikacji:: 2015-02
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 76.60.-k
75.50.Gg
75.50.Tt
75.47.Lx
61.66.Fn
Opis:: Due to their bio-compatibility and non-toxicity, ferrimagnetic iron oxides are suitable for various medical applications. In the case of hyperthermia, the promising approach how to reach desired magnetic properties is to combine more phases into a composite material. A series of samples containing maghemite and M-hexaferrite was prepared by sol-gel method with subsequent thermal treatment where annealing temperature and time were varied. The samples were characterized by X-ray diffraction. In this paper we focused mainly on application of nuclear magnetic resonance spectroscopy to investigate these strongly inhomogeneous nanoparticle composites. Frequency-swept ⁵⁷Fe NMR spectra of nanoparticle samples were measured in a zero external magnetic field at 4.2 K. Utilizing differences in optimal excitation field strengths and in relaxation times, we were able to resolve NMR signal assigned to hexagonal ferrite of M-phase from signal which showed features attributed to maghemite.
Źródło:: Acta Physica Polonica A; 2015, 127, 2; 514-516
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 77.

Tytuł:: The Mössbauer and X-Ray Studies οf the Spinel Ferrites $Cu_{0.5}Fe_{0.5}Cr_2Se_4$ and $Cu_{0.2}Fe_{0.8}Cr_2Se_4$ Prepared by the Ceramic Method
Autorzy:: Maciążek, E.
Hanc, A.
Sitko, R.
Zawisza, B.
Jendrzejewska, I.
Mrzigod, J.
Powiązania:: https://bibliotekanauki.pl/articles/1811603.pdf
Data publikacji:: 2008-12
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 61.05.cp
61.66.Fn
82.80.Ej
75.50.Gg
Opis:: Seleno-spinels with nominal chemical composition $Cu_{0.5}Fe_{0.5}Cr_2Se_4$ and $Cu_{0.2}Fe_{0.8}Cr_2Se_4$ were prepared as polycrystalline samples using ceramic method. The assumed composition was verified by wavelength-dispersive X-ray fluorescence spectrometry. The X-ray analysis was carried out in order to make phase analysis and to compare its results with those obtained with the Mössbauer spectroscopy.
Źródło:: Acta Physica Polonica A; 2008, 114, 6; 1599-1603
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 78.

Tytuł:: Magnetic properties and structure of the Ni-Co-Mn-In alloys with the boron addition
Autorzy:: Prusik, K.
Matyja, E.
Kubisztal, M.
Zubko, M.
Swadźba, R.
Powiązania:: https://bibliotekanauki.pl/articles/1055090.pdf
Data publikacji:: 2017-05
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 81.30.Kf
87.64.Ee
75.50.Ee
75.50.Gg
71.20.Be
Opis:: Series of Ni_{45.5-x}Co_{4.5}Mn_{36.6}In_{13.4}B_{x} (at.%, x=0, 0.05, 0.1, 0.5, 1.0) polycrystalline magnetic shape memory alloys were examined in terms of the magnetic properties, structure and transition temperatures. Depending on the boron concentration single or two phase alloys microstructures were observed. Additionally, the martensitic transformation temperatures decreases with the boron addition. Magnetic-field induced transformation occurs for the alloys with the boron addition up to 0.1 at.%. For alloys with 0.5 and 1.0 at.% of B transformation is hindered.
Źródło:: Acta Physica Polonica A; 2017, 131, 5; 1240-1243
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 79.

Tytuł:: Magnetoelastic Villari Effect in Ferrite Materials for Force and Stress Sensors Working in Low Magnetizing Field Region
Autorzy:: Kachniarz, M.
Bieńkowski, A.
Salach, J.
Szewczyk, R.
Powiązania:: https://bibliotekanauki.pl/articles/1030958.pdf
Data publikacji:: 2018-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.-m
75.60.-d
75.50.Gg
75.80.+q
07.10.Lw
Opis:: The following paper presents the original results of investigation on the magnetoelastic properties of ferrite materials magnetized in low field region, which could be utilized in development of force and stress sensors. The objects of investigation were two ferrite materials (manganese-zinc Mn-Zn and nickel-zinc Ni-Zn). The magnetoelastic characteristics of the materials were investigated with the special measurement system, allowing measurement of magnetic parameters of the ferrite materials magnetized with low fields under the influence of the compressive stress. The obtained results indicate that there is a strong correlation between the magnetic properties of the material in low magnetizing field region, and applied mechanical stress, which allows development of the magnetoelastic stress or force sensor with ferrite core working in low magnetizing field region.
Źródło:: Acta Physica Polonica A; 2018, 133, 4; 1056-1059
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 80.

Tytuł:: Study on the Rayleigh Hysteresis Model and its Applicability in Modeling Magnetic Hysteresis Phenomenon in Ferromagnetic Materials
Autorzy:: Kachniarz, M.
Szewczyk, R.
Powiązania:: https://bibliotekanauki.pl/articles/1030243.pdf
Data publikacji:: 2017-05
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.30.-m
75.60.-d
75.50.Gg
75.50.Cc
75.60.Ej
07.05.Tp
Opis:: The following paper presents the basis of a Rayleigh magnetic hysteresis model and the examples of its application for modeling the magnetic characteristics of ferromagnetic materials: ferrites and steels. The presented model allows one to simulate the shape of a magnetic hysteresis loop of the material for the given value of the magnetizing field in the so-called Rayleigh region, as well as to calculate basic magnetic parameters of the material like coercive field, magnetic remanence, and power loss. Four different ferromagnetic materials (two ferrites and two alloy steels) were chosen for the investigation. Each material was investigated within the range of low magnetizing fields, corresponding to the Rayleigh region. On the basis of obtained results, modeling of magnetic characteristics of the investigated materials was performed. Moreover, the range of magnetizing field where the Rayleigh model can be applied for these materials was investigated based on correlation coefficient between experimental results and modeling.
Źródło:: Acta Physica Polonica A; 2017, 131, 5; 1244-1249
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 81.

Tytuł:: Structural and Magnetic Properties of Nano-Sized NiZn Ferrites
Autorzy:: Ušák, E.
Šoka, M.
Ušáková, M.
Dobročka, E.
Powiązania:: https://bibliotekanauki.pl/articles/1366899.pdf
Data publikacji:: 2014-07
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.50.Tt
61.46.Df
61.05.C-
75.30.Cr
75.75.-c
Opis:: Structural and magnetic properties (such as e.g. size of crystallites, lattice parameter, magnetic susceptibility, Curie temperature, etc.) of nano-sized $Ni_{0.33}Zn_{0.67}Fe_{2}O_{4}$ ferrites have been studied. The obtained results demonstrated that the sintering temperature is an efficient and simple tool for controlling the size of crystallite particles, thus affecting the resulting magnetic properties. Straightforward relationship between the sintering temperature and the size of crystallites was found, meanwhile no other crystalline phases than the spinel one were detected by two independent analytic methods.
Źródło:: Acta Physica Polonica A; 2014, 126, 1; 68-69
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 82.

Tytuł:: Structural Design and Characterization of $BaMg_{x}Co_{2-x}Fe_{16}O_{27}$ Hexaferrites Based on ab initio Computations
Autorzy:: Bakhtiari, M.
Nabiyouni, G.
Besharati-Seidani, A.
Powiązania:: https://bibliotekanauki.pl/articles/1378257.pdf
Data publikacji:: 2014-12
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
71.20.-b
75.75.-c
71.15.Mb
71.15.Dx
Opis:: Structural design of barium hexaferrites $BaMg_xCo_{2-x}Fe_{16}O_{27}$ (x=0.0, 1, 2) has been studied, and the magnetic and electronic structure of that has then been investigated using first principle total energy calculation. All calculations are based on the density functional theory. In order to improve the description of strongly correlated 3d electrons of iron, the general gradient approximation plus Hubbard U (GGA+U) method is used. We found that in the lowest energy configuration Mg and Co ions preferentially occupy the 6g sites. With the increase of Mg content x, the energy gap of $BaMg_xCo_{2-x}Fe_{16}O_{27}$ increases but the lattice constant of unit cell decreases. The magnetic moment of the unit cell for Mg content x=0, 1, and 2 are calculated to be 52, 49 and 46 $μ_{B}$/cell, respectively, in agreement with previous experimental results. The substitutions of Mg and Co at the $BaFe_2^{2+}Fe_{16}^{3+}O_{27}$ decrease electrical conductivity and transit it from a half-metal to semiconductor material. Based on our calculations on electronic band structure, the $BaFe_2Fe_{16}O_{27}$ (BFFO) is a weak half-metal, but $BaMg_2Fe_{16}O_{27}$ (BMFO), $BaMgCoFe_{16}O_{27}$ (BMCFO) and $BaCo_2Fe_{16}O_{27}$ (BCFO) are semiconductors. The electrical resistivity increases by increasing Mg and Co contents due to increase in porosity which prevents the hopping of charge carriers.
Źródło:: Acta Physica Polonica A; 2014, 126, 6; 1288-1292
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 83.

Tytuł:: High-Frequency Absorbing Performances of Carbonyl Iron/MnZn Ferrite/PVC Polymer Composites
Autorzy:: Dosoudil, R.
Ušáková, M.
Powiązania:: https://bibliotekanauki.pl/articles/1032831.pdf
Data publikacji:: 2017-04
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
75.50.Bb
76.50.+g
75.78.-n
72.80.Tm
78.20.Ci
41.20.Jb
Opis:: We have prepared composite materials with a mixture of carbonyl iron (CI) and manganese-zinc ferrite (MnZn) as filler and polyvinylchloride (PVC) as polymer matrix, and then electromagnetic wave absorption properties of CI/MnZn/PVC composites have been studied in the frequency range from 10 MHz to 6.5 GHz. Increasing carbonyl iron loading (to the detriment of MnZn ferrite) results in the rise of permeability and magnetic resonance loss (especially in GHz frequency range) which leads to the shift of absorption peak towards lower frequency and to the decrease of matching thickness. On the contrary, increasing MnZn ferrite loading (to the detriment of carbonyl iron) results in higher absorption bandwidth. The obtained results indicate that the prepared flexible composites may be useful as thin and/or wideband microwave absorbers.
Źródło:: Acta Physica Polonica A; 2017, 131, 4; 687-689
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 84.

Tytuł:: Antisite Defects in Epitaxial Films of Lutetium Doped Yttrium Iron Garnets Studied by Nuclear Magnetic Resonance
Autorzy:: Chlan, V.
Štěpánková, H.
Englich, J.
Řezníček, R.
Kouřil, K.
Kučera, M.
Nitsch, K.
Powiązania:: https://bibliotekanauki.pl/articles/1534129.pdf
Data publikacji:: 2010-11
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 75.50.Gg
76.60.-k
76.60.Lz
68.35.Dv
68.55.Ln
Opis:: Series of lutetium doped yttrium iron garnet films is studied by means of $\text{}^{57}Fe$ nuclear magnetic resonance. Satellite spectral lines are resolved and identified in the spectra and concentrations of lutetium in dodecahedral sites as well as yttrium/lutetium antisite defects in octahedral sites are estimated. Compared to yttrium, lutetium cations are found to have stronger disposition towards creating the antisite defects.
Źródło:: Acta Physica Polonica A; 2010, 118, 5; 846-847
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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Skocz do pozycji: 85.

Tytuł:: Positron Annihilation in $MnFe_2O_4$/MCM-41 Nanocomposite
Autorzy:: Wiertel, M.
Surowiec, Z.
Gac, W.
Budzyński, M.
Powiązania:: https://bibliotekanauki.pl/articles/1339369.pdf
Data publikacji:: 2014-03
Wydawca:: Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:: 78.70.Bj
34.80.Lx
78.67.Bf
62.23.Pq
68.43.-h
75.50.Gg
78.47.D-
Opis:: In the paper results of studies of $MnFe_2O_4$/MCM-41 nanocomposites have been presented. The influence of manganese ferrite loading on changes of porous properties of mesoporous MCM-41 structure was studied by means of $N_2$ sorption/desorption method and positron annihilation lifetime spectroscopy. Disappearance of the longest-lived ortho-positronium component ($τ_5$) of pure MCM-41 mesoporous material in the positron annihilation lifetime spectra of $MnFe_2O_4$/MCM-41 measured in vacuum is a result of either o-Ps quenching or the Ps inhibition mechanism. Filling of pores in the studied nanocomposites by air at ambient pressure causes partial reappearance of the ($τ_5$) component except for the sample with maximum ferrite content. Both the ($τ_5$) component lifetime and intensity are suppressed together with increasing $MnFe_2O_4$ content by chemical quenching and inhibition of Ps formation occur. Observed anti-quenching effect of air is a result of two processes: neutralization of some surface active centres acting as inhibitors and considerably weaker paramagnetic quenching by $O_2$ molecules.
Źródło:: Acta Physica Polonica A; 2014, 125, 3; 793-797
0587-4246
1898-794X
Pojawia się w:: Acta Physica Polonica A
Dostawca treści:: Biblioteka Nauki

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