Informacja

Drogi użytkowniku, aplikacja do prawidłowego działania wymaga obsługi JavaScript. Proszę włącz obsługę JavaScript w Twojej przeglądarce.

English (EN)·Polski (PL)·Yкраїнський (UK)
Przejdź do strony domowej biblioteki Centralna Biblioteka Wojskowa Link otwiera się w nowym oknie Logo biblioteki Prolib Integro - strona głównaCentralna Biblioteka Wojskowa

Wyszukujesz frazę "74.70.-b" wg kryterium: Temat

  Lista filtrów
Wyrównaj
Wyświetlanie 1-15 z 28
Tytuł:
Electron-Molecular Vibration Coupling in TTF-Based Donors
Autorzy:
Pokhodnia, K. I.
Powiązania:
https://bibliotekanauki.pl/articles/1933373.pdf
Data publikacji:
1995-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
Opis:
BEDT-TTF, BMDT-TTF and BEDO-TTF are well known thio-TTF and oxo-TTF (in the former case) derivatives on the basis of which cation-radical salts with 2D type of conductivity can be produced. In this work the comparative analysis of electron-molecular vibration coupling constants (obtained by MNDO quantum-chemical method) that describe the interaction between totally symmetric A$\text{}_{g}$ modes and electron on HOMO level is performed.
Źródło:
Acta Physica Polonica A; 1995, 87, 4-5; 815-818
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Synthesis and Characterization of the Superconductor $Mo_3Sb_7$
Autorzy:
Tran, V.
Bukowski, Z.
Powiązania:
https://bibliotekanauki.pl/articles/1812274.pdf
Data publikacji:
2008-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.25.Bt
74.70.-b
Opis:
We synthesized a polycrystalline sample of the superconductor $Mo_3Sb_7$ and characterized its basic properties by measurements of magnetization, electrical resistivity and specific heat. The measurements establish a superconducting phase transition at $T_c$=2.25 (0.05) K. In applied magnetic fields, the magnetization and resistivity show the behavior of type-II superconductor. From the specific heat measurement, the electronic specific heat coefficient,γ, specific heat jump at $T_c,$ $ΔC(T_c)//γT_c,$ and the Debye temperature $Θ_D$, are evaluated to be 34.5 mJ/(mol $K^2$), 1.56 and 283 K, respectively. From analysis of the specific heat data we suggest that this compound belongs to an intermediate strong coupling regime in the BCS context. The observed enhancement in theγ-value suggests a substantial contribution of Mo-4d-electrons to the density of states. Our experimental data do not support interpretation of superconductivity in $Mo_3Sb_7$ in terms of neither unconventional superconductivity or spin fluctuations proposed previously.
Źródło:
Acta Physica Polonica A; 2008, 114, 1; 67-74
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Superconductivity of $MgB_2$ Layers Prepared on Silicon Substrate by Implantation of Magnesium Ions into Boron Substrate
Autorzy:
Trybuła, Z.
Kempiński, W.
Łoś, Sz.
Kaszyńska, K.
Trybuła, M.
Piekoszewski, J.
Werner, Z.
Barlak, M.
Powiązania:
https://bibliotekanauki.pl/articles/1536977.pdf
Data publikacji:
2010-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
74.78.-w
Opis:
The results of investigation of the $MgB_2$ layers prepared on silicon substrate by implantation of Mg ions into boron substrate are presented. After implantation the annealing processes were carried out at temperatures 673 K, 773 K, and 873 K in a furnace in an atmosphere of flowing Ar-4%$H_2$ gas mixture. The samples were characterized by: four-probe electric conductivity measurements and magnetically modulated microwave absorption. Our results showed that due to silicon substrate the diffusion of implanted Mg ions into boron materials should be limited, and the superconducting phase forms a continuous $MgB_2$ layer and the resistivity for all samples fall down to zero below $T_{c}$. The transition temperature $T_{c}$ becomes higher with increasing annealing temperature: $T_{c}$=18 K (for annealing at $T_{A}$=673 K), $T_{c}$=20 K (for annealing at $T_{A}$=773 K), and $T_{c}$=27 K (for annealing at $T_{A}$=873 K).
Źródło:
Acta Physica Polonica A; 2010, 118, 2; 323-325
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Evolution of Superconducting Phase $MgB_x$
Autorzy:
Łoś, Sz.
Kempiński, W.
Piekara-Sady, L.
Andrzejewski, B.
Jurga, W.
Kaszyńska, K.
Piekoszewski, J.
Werner, Z.
Barlak, M.
Powiązania:
https://bibliotekanauki.pl/articles/1812318.pdf
Data publikacji:
2008-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
74.78.-w
Opis:
Thin layers of $MgB_x$ were studied in order to define evolution of superconducting phase after Mg ions implantation into boron substrate. Three fluencies of energies 140, 80, and 40 keV were used to establish proper stoichiometry to synthesize homogeneous $MgB_2$ film. Additionally, the annealing processes were carried out at temperatures 400, 500, and 600°C in a furnace in an atmosphere of flowing $Ar-4%H_2$ gas mixture. The quality of the superconducting material was examined by magnetically modulated microwave absorption, and magnetic and resistivity measurements. The results showed that $T_c$ becomes higher with increasing annealing temperature. However, the fraction of superconducting phase decreases, due to partial evaporation of Mg ions and their deeper migration into boron substrate.
Źródło:
Acta Physica Polonica A; 2008, 114, 1; 179-184
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ion Implantation and Transient Melting: A New Approach to Formation of Superconducting MgB$\text{}_{2}$ Phases
Autorzy:
Piekoszewski, J.
Kempiński, W.
Stankowski, J.
Prokert, F.
Richter, E.
Stanisławski, J.
Werner, Z.
Szymczyk, W.
Powiązania:
https://bibliotekanauki.pl/articles/2041609.pdf
Data publikacji:
2004-12
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
74.78.-w
Opis:
An attempt to synthesize superconducting MgB$\text{}_{2}$ inter-metallic compound from the liquid state is presented. The process consists of two steps. In the first one, boron ions are implanted into a magnesium substrate. In the second one, the near-surface region of such system is melted by short, intense hydrogen plasma pulses without necessity of annealing in Mg vapor. A magnetically modulated microwave absorption method was used to detect superconducting regions in the obtained MgB$\text{}_{2}$ layer. Percolation between nano-regions (islands) of MgB$\text{}_{2}$ has not been observed. However, a superconducting state of the insulated islands has been experimentally proven with transition temperatures T$\text{}_{C}$ as high as 31 K.
Źródło:
Acta Physica Polonica A; 2004, 106, 6; 861-868
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Formation of Superconducting Regions of MgB_2 by Implantation of Boron Ions into Magnesium Substrate
Autorzy:
Trybuła, Z.
Kempiński, W.
Andrzejewski, B.
Piekara-Sady, L.
Kaszyński, J.
Piekoszewski, J.
Werner, Z.
Richter, E.
Prokert, F.
Stanisławski, J.
Barlak, M.
Powiązania:
https://bibliotekanauki.pl/articles/2043433.pdf
Data publikacji:
2005-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
74.78.-w
Opis:
The results of investigation of the MgB$\text{}_{2}$ inter-metallic compound with the use of boron ions implantation and plasma pulse treatment are presented. The samples were characterized by: four-probe electric conductivity measurements, magnetically modulated microwave absorption, and magnetic measurements. For hydrogen and argon pulsed plasma treatment the samples with T$\text{}_{c}$ ranging from 10 K to 32 K were obtained. The superconducting phase does not form a continuous layer since the resistivity does not fall down to zero. Apparently, separate islands of superconducting phase are connected through metallic Mg paths. All samples are still below the percolation threshold.
Źródło:
Acta Physica Polonica A; 2005, 108, 1; 165-170
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Superconducting Regions and Kondo Effect of MgB$\text{}_{2}$ Formed by Implantation of Magnesium Ions into Boron Substrate
Autorzy:
Trybuła, Z.
Kempiński, W.
Andrzejewski, B.
Piekara-Sady, L.
Kaszyński, J.
Trybuła, M.
Piekoszewski, J.
Stanisławski, J.
Barlak, M.
Richter, E.
Powiązania:
https://bibliotekanauki.pl/articles/2046803.pdf
Data publikacji:
2006-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
74.78.-w
Opis:
The results of investigation of the polycrystalline boron implanted by magnesium and argon plasma pulse treatment are presented. The four-probe electric conductivity measurements and magnetically modulated microwave absorption showed the presence of superconducting islands below the temperature of 25 K. Below T=23 K we detected the Kondo effect, a logarithmic increase in the resistivity as the temperature is lowered, due to iron impurity.
Źródło:
Acta Physica Polonica A; 2006, 109, 4-5; 657-660
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Critical Behaviour of Pyroelectric-Type Superconductors
Autorzy:
Krzyżanowski, I. H.
Powiązania:
https://bibliotekanauki.pl/articles/1887981.pdf
Data publikacji:
1991-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
67.50.-b
74.70.-b
Opis:
The quasiclassical, Eilenberger-type equations are applied to description of rotating P-wave pyroelectric-type superconductor in the presence of magnetic field H and superflow υ. In analogy to type-II superconductors the possibility of vortex solution is discussed. We determine the symmetry of eigensolutions and the upper critical velocity Ω$\text{}_{c2}$. We discuss the paramagnetic critical behaviour of the system depending on the strength of spin-orbit interaction.
Źródło:
Acta Physica Polonica A; 1991, 80, 1; 81-98
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Electronic Properties of High-Temperature Superconductor DyBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7}$ from Critical Fields and Specific Heat Studies
Autorzy:
Kołodziejczyk, A.
Kozłowski, A.
Chmist, J.
Zalecki, R.
Ściężor, T.
Tarnawski, Z.
Woch, W. M.
Powiązania:
https://bibliotekanauki.pl/articles/1929388.pdf
Data publikacji:
1993-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
76.30.-v
Opis:
The lower and upper critical fields, as well as the specific heat were measured as a function of temperature for good quality DyBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7}$ high-temperature superconductor in the vicinity of superconducting transition temperature T$\text{}_{c}$ = 91.2 K. The number of superconducting and normal state electronic quantities were determined basing on the Ginzburg-Landau-Abrikosov-Gorkov theory. It is argued that on the basis of this BCS-like theory one can describe the superconducting properties and, in combination with some information on the electronic structure, also the magnetic properties of high-temperature superconductors.
Źródło:
Acta Physica Polonica A; 1993, 84, 1; 127-138
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
On the Surfacegrived State of Cleaved YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$ Single Crystals
Autorzy:
Harm, S.
Mante, G.
Manzke, R.
Fink, J.
Skibowski, M.
Powiązania:
https://bibliotekanauki.pl/articles/1920917.pdf
Data publikacji:
1992-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
79.60.-i
Opis:
Angle-resolved photoemission experiments on the cleaved surface of YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$ single crystals revealed an intrinsic surface-derived electronic state around the X and Y point of the Brillouin zone with 0.92 eV binding energy. A surface electronic structure different to the bulk can be of basic importance for the surface superconductivity of this high-T$\text{}_{c}$ cuprate. Here we briefly review recent experimental results and present new hydrogen adsorption experiments, demonstrating the surface character of the 0.92 eV state.
Źródło:
Acta Physica Polonica A; 1992, 82, 2; 349-354
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Comparison of the Temperature Dependence of the Crystal Structure of $LiTi_2O_4$ and $LiV_2O_4$
Autorzy:
Moshopoulou, E.
Powiązania:
https://bibliotekanauki.pl/articles/1813759.pdf
Data publikacji:
2008-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
61.05.fm
Opis:
The normal spinel oxide $LiTi_2O_4$ is an exotic superconductor with $T_c$=11.2 K, while the isostructural neighbouring $LiV_2O_4$ exhibits heavy-fermion behaviour. The origin of their physics and the role of the spinel structure on their properties are yet unsolved issues, owing mainly to the complexity of the structure, the presence of subtle disorder, and the sample dependence of the physical properties. Especially and perhaps more importantly, the enormous difference in their low-temperature properties remains an open question. This question has only been addressed theoretically but (mainly because of the above problems) there were no experimental studies that sought to understand the clearly distinct behaviour of the two systems. Here, we contribute to the understanding of such distinct low-temperature behaviour by comparing the temperature dependence of the very basic structural properties of the two systems. Upon cooling from room temperature, the lattice parameter a decreases gradually in about the same way for both systems. However, below 20 K, a clear decrease in a of $LiV_2O_4$ as a function of temperature contrasts strongly with the almost constant value of a of $LiTi_2O_4$ in the same temperature range. Therefore subtle but clearly different structural signatures are coupled with the very divergent physical properties of the two systems and suggest new directions to the theory.
Źródło:
Acta Physica Polonica A; 2008, 113, 1; 399-402
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
XANES Experiments for High-Temperature Superconductors
Autorzy:
Kołodziejczyk, A.
Powiązania:
https://bibliotekanauki.pl/articles/1920888.pdf
Data publikacji:
1992-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
76.30.-v
Opis:
The paper presents the results of XANES (X-ray Absorption Near Edge Structure) experiments, of the high-temperature superconductors of Y-Ba-Cu-O-type carried out at the Cu L$\text{}_{II,III}$- and O K$\text{}_{I}$-edges using synchrotron radiation and the KMC double monochromator and SX-700 grading monochromator beamlines of BESSY/Berlin synchrotron storage ring. The aim of the paper is to show that the XANES studies are well suited for characterization of the local electronic structure of the high-temperature superconductors.
Źródło:
Acta Physica Polonica A; 1992, 82, 2; 273-281
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Specific Heat of RBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-x}$ and RBaSrCu$\text{}_{3}$O$\text{}_{7-x}$ Compounds (R = Sm, Dy, Er)
Autorzy:
Tarnawski, Z.
Kim-Ngan, N.-T. H.
Wang, X. Z.
Duijn, V. H. M.
Franse, J. J. M.
Powiązania:
https://bibliotekanauki.pl/articles/1968860.pdf
Data publikacji:
1998-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
75.40.-s
Opis:
The low-temperature specific-heat C(T) data of high-T$\text{}_{c}$ superconductors RBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-x}$(R123O$\text{}_{7-x}$) were reviewed. A discussion of the C(T) data obtained on single-crystalline samples of Er123O$\text{}_{7-x}$ and Sm123O$\text{}_{7-x}$ compounds in applied magnetic fields for better evaluation of the crystal-electric-field parameters is given. The C(T) measurements of Sr-substituted compounds RBaSrCu$\text{}_{3}$O$\text{}_{7}$ revealed the λ-type of peak related to the antiferromagnetic order at 1.2 K and 0.6 K respectively for Dy- and Er-compounds. The magnetic singlet ground state in these compounds is produced by weak exchange interactions of -0.05 T/μ$\text{}_{B}$ and -0.035 T/μ$\text{}_{B}$, respectively. For Nd- and Sm-compounds, only a broad anomaly around 0.6 K was observed which is well fitted with a Schottky-type anomaly with an energy splitting of 1.4 K.
Źródło:
Acta Physica Polonica A; 1998, 93, 3; 513-522
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Magnetic Properties of Milled and Thermal Relaxed YBa$\text{}_{2}$ (Cu$\text{}_{1-x}$Fe$\text{}_{x}$)$\text{}_{3}$O$\text{}_{y}$
Autorzy:
Timko, M.
Kováč, J.
Sargánková, I.
Zentková, M.
Mihalik, M.
Maťaš, S.
Čiasnohová, A.
Powiązania:
https://bibliotekanauki.pl/articles/1955517.pdf
Data publikacji:
1997-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.90.+n
74.10.+v
74.70.-b
Opis:
The influence of the mechanical milling and subsequent thermal relaxation on magnetic and superconducting behaviour of YBa$\text{}_{2}$(Cu$\text{}_{1-x}$Fe $\text{}_{x}$)$\text{}_{3}$O$\text{}_{y}$ system has been studied. Two methods of heat treatment were used: Set I - slow cooling from 980°C in flowing O$\text{}_{2}$ and Set II - reducing at 770°C in flowing Ar$\text{}_{2}$ followed by reoxidation in flowing O$\text{}_{2}$ below 400°C. The transition to superconductivity, diamagnetic response, critical current density and the effective magnetic moment in the normal state have been estimated. Our measurements indicate that the reducing atmosphere preparation is less detrimental on superconducting properties. The results are discussed in terms of occupancy Cu sites by Fe and redistribution of oxygen atoms.
Źródło:
Acta Physica Polonica A; 1997, 91, 2; 355-358
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Microwave Absorption Study on (Bi,Pb)-Sr-Ca-Cu-O Granular Superconductors
Autorzy:
Jurga, W.
Piekara-Sady, L.
Gazda, M.
Powiązania:
https://bibliotekanauki.pl/articles/1812335.pdf
Data publikacji:
2008-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.-b
74.72.-h
74.45.+c
Opis:
(Bi,Pb)-Sr-Ca-Cu-O is considered as a system of 2201, 2212 and 2223 superconductors embedded in the insulating matrix. The size of the grains depends on the time of recrystallization. These types of ceramics exhibit a two-step transition to superconducting state. Because electrical properties depend among other on the Josephson coupling between grains, the magnetically modulated microwave absorption study was undertaken. Magnetically modulated microwave absorption signal was observed to arise just as temperature had been lowered below T₁. The shape of this signal was studied to recognize the second temperature T₂. Some strong oscillations appear on magnetically modulated microwave absorption at lower temperatures, which might be related to local percolation breakdown in superconducting network.
Źródło:
Acta Physica Polonica A; 2008, 114, 1; 253-256
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 28

Ta witryna wykorzystuje pliki cookies do przechowywania informacji na Twoim komputerze. Pliki cookies stosujemy w celu świadczenia usług na najwyższym poziomie, w tym w sposób dostosowany do indywidualnych potrzeb. Korzystanie z witryny bez zmiany ustawień dotyczących cookies oznacza, że będą one zamieszczane w Twoim komputerze. W każdym momencie możesz dokonać zmiany ustawień dotyczących cookies