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 "74.72.-h" wg kryterium: Temat

  Lista filtrów
Wyrównaj
Wyświetlanie 1-15 z 83
Tytuł:
XPS Study of "infinite Chain" Ca$\text{}_{2}$CuO$\text{}_{3}$ and Ca$\text{}_{0.5}$Sr$\text{}_{0.5}$CuO$\text{}_{2}$ Compounds
Autorzy:
Jacyna-Onyszkiewicz, I.
Poltoracky, Yu. B.
Powiązania:
https://bibliotekanauki.pl/articles/2013234.pdf
Data publikacji:
2000-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
79.60.-i
74.72.-h
74.72.Jt
Opis:
Al K$\text{}_{α}$ excited photoelectron spectra (X-ray photoelectron spectroscopy) of the O 1s, Cu 2p, Ca 2p, Sr 3d core levels were measured for "infinite chain" Ca$\text{}_{2}$CuO$\text{}_{3}$ and Ca$\text{}_{0.5}$Sr$\text{}_{0.5}$CuO$\text{}_{2}$ compounds. The analysis indicates that for Ca$\text{}_{2}$CuO$\text{}_{3}$ the surface electronic structure is strongly influenced by a humid atmosphere. The surface layer is formed predominantly by copper hydroxide. The minor features of Cu 2p and O 1s are characteristic of the bulk bonding states. The valences of the Cu, Ca, and Sr atoms are close to 2+. The core electron binding energies (≈ 934 eV peak) are due to the 2p$\text{}_{3}\text{}_{/}\text{}_{2}$ 3d$\text{}^{10}$L$\text{}^{1}$ configuration of Cu(II) ions in the square planar coordination for both samples.
Źródło:
Acta Physica Polonica A; 2000, 97, 3; 603-606
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Vortex Motion and Quasiparticle Resistivity in Superconductors at Microwave Frequencies
Autorzy:
Sarti, S.
Amabile, C.
Fastampa, R.
Giura, M.
Silva, E.
Pompeo, N.
Powiązania:
https://bibliotekanauki.pl/articles/2047225.pdf
Data publikacji:
2007-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.25.Nf
74.20.De
74.60.Ge
74.70.Ad
74.72.-h
Opis:
At nonzero frequencies both the normal and superfluid fractions, as well as moving vortices, contribute to the electrical transport, resulting in intricate expressions for the resistivity. We present an extended study of microwave resistivity data measured on YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$, SmBa$\text{}_{2}$ Cu$\text{}_{3}$O$\text{}_{7-δ}$, and MgB$\text{}_{2}$ by means of a broad-band technique between 2 and 20 GHz and of a resonant system at 50 GHz. We discuss the main experimental fingerprints that allow one to identify the relevance of the different contributions from the measured microwave response as a function of frequency, temperature, and magnetic field. We show that the field-dependent superfluid/quasiparticles dynamics cannot be in general neglected with respect to the vortex motion, albeit its relative importance is different in different materials: in high temperature superconductors vortex motion prevails at high fields, but at low fields a significant superfluid/quasiparticle contribution exists (ascribed to the presence of lines of nodes). In MgB$\text{}_{2}$ the two contributions are comparable even at high fields. In this general frame, we derive from the measurements vortex and superfluid parameters in agreement with theoretical predictions and independent measurements.
Źródło:
Acta Physica Polonica A; 2007, 111, 1; 87-93
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Universal Critical Quantum Properties of Cuprate Superconductors
Autorzy:
Schneider, T.
Powiązania:
https://bibliotekanauki.pl/articles/1953179.pdf
Data publikacji:
1997-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.62.-c
74.72.-h
74.62.Dh
74.25.-q
Opis:
Using the scaling theory of quantum critical phenomena we explore the occurrence of universal critical behavior at the insulator-to-superconductor and superconductor-to-normal state transitions at zero temperature. Experimentally, these phase transitions are driven by doping and correspond to critical end points of the phase transition line in the temperature-hole concentration plane. Provided that the order parameter is a complex scalar in two dimensions, and that the London relation between superfluid number density and magnetic penetration depth holds, the scaling theory predicts universal behavior close to the insulator-to-superconductor transition. In particular, transition temperature and zero temperature penetration depth are universally related and the sheet resistance adopts a universal value. These predictions agree remarkably well with available experimental data and provide useful constraints for a microscopic theory.
Źródło:
Acta Physica Polonica A; 1997, 91, 1; 203-212
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Unidirectional Charge Instability of the d-Wave Resonating Valence Bond Superconductor
Autorzy:
Raczkowski, M.
Capello, M.
Poilblanc, D.
Powiązania:
https://bibliotekanauki.pl/articles/1810295.pdf
Data publikacji:
2009-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.72.-h
74.20.Mn
74.81.-g
75.40.Mg
Opis:
Starting from a uniform d-wave superconducting phase we study the energy cost due to imposed unidirectional defects with a vanishing pairing amplitude. Both renormalized mean-field theory and variational Monte Carlo calculations within the t-J model yield that the energies of inhomogeneous and uniform phases are very close to each other. This suggests that small perturbations in the microscopic Hamiltonian might lead to inhomogeneous superconducting phases in real materials as observed in recent scanning tunneling microscopy on $Ca_{2-x}Na_xCuO_2Cl_2$.
Źródło:
Acta Physica Polonica A; 2009, 115, 1; 77-79
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Ultrafast Dynamics of Photoinduced Electronic Phase Modulation in Ladder Cuprate of $Sr_{14 - x}Ca_{x}Cu_{24}O_{41}$
Autorzy:
Fukaya, R.
Kunitomo, M.
Okimoto, Y.
Ishikawa, T.
Onda, K.
Koshihara, S.
Yui, H.
Sasagawa, T.
Powiązania:
https://bibliotekanauki.pl/articles/1489955.pdf
Data publikacji:
2012-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
78.47.-p
74.72.-h
78.20.-e
Opis:
Ultrafast carrier dynamics caused by photoexcitation in quasi-one-dimensional two-leg ladder cuprate $Sr_4Ca_{10}Cu_{24}O_{41}$ was investigated by the femtosecond reflection spectroscopy. After the photoexcitation along the leg direction, the transient reflectivity changes (Δ R/R) in the mid-infrared region showed instant decrease within 150 fs. The suppressed Δ R/R increased so rapidly on the picosecond time scale that the reflectivity value finally became larger than that in the initial state. Such a successive response in Δ R/R, which was also observed in other photon energy regions, is discussed in terms of ultrafast variation of the Drude weight in the ladder system by the photoirradiation.
Źródło:
Acta Physica Polonica A; 2012, 121, 2; 310-312
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Trapped field of YBCO bulk superconductors prepared by infiltration growth process
Autorzy:
Vojtkova, L.
Diko, P.
Piovarči, S.
Powiązania:
https://bibliotekanauki.pl/articles/1054776.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.72.-h
74.81.Bd
61.50.-f
74.25.Ha
81.10.Fq
Opis:
Single grain Y₁Ba₂Cu₃O_{7-x} (YBCO) bulk superconductors were prepared from different starting precursors. In the first case, Y₂Ba₁Cu₁O₅ (Y211) powder as the solid phase and the liquid phase of mixture of YBa₂Cu₃O_{7-x}+BaCuO₂+CuO powders were used. In the second case, the solid phase was prepared from the mixture of Y₂O₃+BaCuO₂ instead of the conventionally used Y211, and as the liquid phase a mixture of Y₂O₃+BaCuO₂+CuO powders was used. The trapped field measurements at 77 K were performed and microstructure of samples was studied by polarized light microscopy. The positive influence of Y₂O₃+BaCuO₂ starting precursor on the oxygenation, Y211 particle refinement and measured trapped field is shown.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 1048-1050
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermal Fluctuations of Bismuth Based 1G Tape
Autorzy:
Chrobak, M.
Woch, W.
Zalecki, R.
Kołodziejczyk, A.
Powiązania:
https://bibliotekanauki.pl/articles/1385435.pdf
Data publikacji:
2015-02
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.72.-h
74.78.-w
74.40.-n
74.62.-c
Opis:
The thermal fluctuations of bismuth based commercial 1G tape were studied near the critical temperature $T_{c}$=110.2 K. The detailed analysis of the temperature dependence of resistivity measurements was made in the temperature region from the zero resistance critical temperature up to 300 K. The thermal fluctuations of conductivity were analysed using the Aslamazov-Larkin microscopic approach and the critical exponents were calculated close to the transition temperature.
Źródło:
Acta Physica Polonica A; 2015, 127, 2; 306-308
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermal Fluctuations of $(Tl_{0.5}Pb_{0.5})Sr_2(Ca_{0.9}Gd_{0.1})Cu_2O_{z}$ Bulk Superconductor
Autorzy:
Woch, W.
Chrobak, M.
Kołodziejczyk, A.
Gritzner, G.
Powiązania:
https://bibliotekanauki.pl/articles/1426876.pdf
Data publikacji:
2012-05
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.72.-h
74.40.-n
74.20.De
74.25.Ha
Opis:
We report on the critical fluctuations from the magnetoresistance measurements in polycrystalline $(Tl_{0.5}Pb_{0.5})Sr_2(Ca_{0.9}Gd_{0.1})Cu_2O_{z}$ superconductor. The critical exponents have been calculated above the critical temperature $T_{c}$ as well as in the temperatures interval close to the zero resistance critical temperature. Above $T_{c}$ only Gaussian fluctuations have been observed in a three-dimensional fluctuating system. Additionally, far above $T_{c}$ the applied magnetic field induces the crossover from 3D to 2D fluctuating system. At the temperatures range close to the zero critical temperature the properties of the weak links are dominating and the fluctuating phase in each grain becomes long-range ordered as a consequence of the activation of weak links between grains.
Źródło:
Acta Physica Polonica A; 2012, 121, 5-6; 1059-1062
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Thermal Fluctuations in YBCO Thin Film on MgO Substrate
Autorzy:
Chrobak, M.
Woch, W.
Szwachta, G.
Zalecki, R.
Gondek, Ł.
Kołodziejczyk, A.
Kusiński, J.
Powiązania:
https://bibliotekanauki.pl/articles/1374789.pdf
Data publikacji:
2014-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.72.-h
74.78.-w
74.40.-n
74.62.-c
Opis:
The c-axis orientation $YBa_2Cu_3O_δ$ thin film was prepared directly on MgO substrate by the pulse laser deposition. The thickness of the film was 170 nm. The superconducting critical temperature was $T_{c50%}$=89 K and the width of superconducting transition was Δ T= 1.6 K. Temperature dependence of the critical current of the film was obtained from the temperature dependences of the imaginary part of the AC susceptibility using the Bean model. The critical current density was $J_{c}$=1.2×$10^7$ A/$cm^{2}$ at 77 K in the self field. The critical exponents were calculated for several values of the DC applied magnetic field using the temperature dependences of magnetoresistivity. The thermal fluctuations in vicinity of the critical temperature were analysed.
Źródło:
Acta Physica Polonica A; 2014, 126, 4a; A-88-A-91
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Theoretical Study on the Pressure Induced $T_c$ Change in $YBa_2Cu_3O_x$
Autorzy:
Milić, M.
Powiązania:
https://bibliotekanauki.pl/articles/1399323.pdf
Data publikacji:
2013-10
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.62.Fj
74.72.-h
Opis:
Pressure effect on the critical temperature, $T_{c}$, of the $YBa_2Cu_3O_x$ superconductor was considered in the frame of a simple theoretical model which as a starting point assumes that $T_{c}$ vs. pressure, P, dependence can be described by an inverted parabola. Available experimental results on $T_{c}$ behavior under pressure were analyzed as a function of the zero pressure hole concentration in the superconducting $CuO_2$ planes, $n_{h}(P = 0 GPa) = n_{h0}$, for different constant values of P. Maximum $T_{c}$ that can be achieved under pressure was estimated and discussed in relation to the $n_{h0} = 1//8$ doping and establishment of charge and spin order. The results obtained here were used to estimate increase of the hole concentration in the $CuO_2$ planes which occurs as a result of pressure induced oxygen reordering.
Źródło:
Acta Physica Polonica A; 2013, 124, 4; 745-749
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Superconducting and Magnetic States in $RuSr_2GdCu_2O_8$, Based on the Magnetic, Transport and Magneto-Caloric Characteristics
Autorzy:
Klamut, P.
Plackowski, T.
Powiązania:
https://bibliotekanauki.pl/articles/1536600.pdf
Data publikacji:
2010-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.72.-h
75.30.-m
74.62.Bf
74.25.F-
75.30.Sg
Opis:
The article discusses selected properties of the non- and superconducting polycrystalline samples of $RuSr_2GdCu_2O_8$ and comments on the consequences of introducing insignificant sub-stoichiometry of Ru into the nominal formula. The magneto-resistive and the magnetic characteristics are interpreted in favour of the formation of intrinsically inhomogeneous superconducting phase, which seems stabilized along with the structural modifications enhanced with the modification of starting stoichiometry. The specific heat data reveals the small shift of the temperature of magnetic ordering $T_{m}$, which may suggest dilution of the magnetic sublattice of the Ru moments. The measurements of the magnetic field dependences of the isothermal magnetocaloric coefficient $M_{T}$ reveal no gain in the system magnetic entropy in a broad range of accessed fields and temperature. Whereas the multi-component character of the compound's magnetsm precludes from concluding on the magnetic ground state, the maximum in $M_T (H)$, which occurs at comparably weak magnetic field for temperatures in a vicinity of $T_{m}$ may reflect dominance of the ferromagnetic type interactions with a constrained correlation range. The literature explored models for the Ru magnetic ordering and also possible phase separation are brought into the discussion.
Źródło:
Acta Physica Polonica A; 2010, 118, 2; 254-260
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Primary Role of Ionic Polarizability in Exotic Superconductivity
Autorzy:
Weger, M.
Powiązania:
https://bibliotekanauki.pl/articles/1933315.pdf
Data publikacji:
1995-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.70.Kn
74.72.-v
72.15.-h
71.45.Gm
Opis:
The ionic polarizability of organic metals and of high-T$\text{}_{c}$ cuprates is very high while the density of conduction electrons is low. As a result, the ionic polarizability screens out the electronic polarizability for states very close to the Fermi surface. The cut-off is determined by the dispersion of the ionic polarizability. The electron-phonon matrix element is very large for the ionically screened states, and is the cut-off for the electronically screened states. Therefore, the McMillan coupling constant λ$\text{}_{ph}$ is very large at very low energies, and has a low energy cut-off. This model accounts for both normal and superconducting state anomalies in organic metals, as well as cuprates.
Źródło:
Acta Physica Polonica A; 1995, 87, 4-5; 723-733
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Local Order in KTaO$\text{}_{3}$ Admixtured by the Ions of Li$\text{}^{+}$
Autorzy:
Kaszyńska, K.
Trybuła, Z.
Glinchuk, M. D.
Bykov, I. P.
Laguta, V. V.
Powiązania:
https://bibliotekanauki.pl/articles/2043642.pdf
Data publikacji:
2005-08
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
64.70.-p
36.40.Ei
77.22.Gm
74.72.-h
74.76.Bz
Opis:
The low temperature behavior of the KTaO$\text{}_{3}$ type incipient ferroelectric crystals is of constant interest. The quantum fluctuations reduce the transition to the ferroelectric state in these crystals. It is possible that the small amount of the dopant Li$\text{}^{+}$ can lead, through the elastic interactions, to local glass-like short-range order or even to the relaxor ferroelectric order for x>2.6%. We presented that the low lithium doped x=0.005 KTaO$\text{}_{3}$ crystals exhibit the dielectric dispersion ofε andε", suggesting the glass-like behavior in the low temperature range.
Źródło:
Acta Physica Polonica A; 2005, 108, 2; 379-383
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The Influence of the Pinning Centres Dimensions on the Critical Current in High-T$\text{}_{c}$ Superconductors
Autorzy:
Sosnowski, J.
Powiązania:
https://bibliotekanauki.pl/articles/2041525.pdf
Data publikacji:
2004-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.25.Qt
74.72.-h
Opis:
An analysis of the influence of the pinning centres dimensions on the critical current and pinning forces of the high temperature oxide superconductors is presented. Individual interaction of the pinning centres with pancake type vortices is considered for the layered structure of the copper-oxide superconductors. The phenomenological model was elaborated in which the change of the system energy has been constructed taking into account the pinning interaction, Lorentz forces, and elastic energy of the vortex lattice. The resistivity criterion has been used for detection of the critical current. Especially important results have been obtained for the range of the pinning centres dimensions smaller than twice the value of the coherence length.
Źródło:
Acta Physica Polonica A; 2004, 106, 5; 767-770
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
The effect of Sm addition on the microstructure and superconducting properties of YBCO bulk superconductors
Autorzy:
Volochová, D.
Diko, P.
Piovarči, S.
Antal, V.
Kováč, J.
Jirsa, M.
Powiązania:
https://bibliotekanauki.pl/articles/1054772.pdf
Data publikacji:
2017-04
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.72.-h
74.62.Dh
81.10.Fq
61.72.-y
74.25.Ha
74.25.Sv
Opis:
The effect of Sm addition on the microstructure and superconducting properties of Y-Ba-Cu-O (YBCO) bulk superconductors has been studied. Nominal composition: 1 mol YBa₂Cu₃O_{7-δ} + 0.25 mol Y₂O₃ + 1 wt% CeO₂ was enriched with different amounts of SmBa₂Cu₃O_y powder with the aim to increase critical current density, J_c, especially in higher magnetic fields by introducing additional pinning centers. Single grain YBCO bulk superconductors with SmBa₂Cu₃O_y (Y123-Sm) addition were prepared by the optimized top seeded melt growth process. Microstructure analysis, performed by polarized light microscope, revealed that SmBa₂Cu₃O_y addition leads to a higher amount of slightly coarser Y₂BaCuO₅ particles, which is related to lower critical current densities (J_c ≈ 6×10⁴ A/cm²) of the YBCO samples with SmBa₂Cu₃O_y addition in low magnetic fields. On the other hand, an enhancement of critical current density, J_c, in higher magnetic fields was observed for Y123-Sm samples. Moreover, a maximum trapped magnetic field, B_{tmax}, of 564 mT at 77 K in Y123-Sm, x=0.0025 sample (Ø 17.2 mm) was 43% higher than that for YBCO sample without any addition.
Źródło:
Acta Physica Polonica A; 2017, 131, 4; 1009-1011
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Wyświetlanie 1-15 z 83

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