Informacja

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

Wyszukujesz frazę "H62" wg kryterium: Temat


Wyświetlanie 1-11 z 11
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:
Structural Determination of Epitaxial Formations in Layered Cuprates
Autorzy:
Leonyuk, L.
Maltsev, V.
Babonas, G.-J.
Powiązania:
https://bibliotekanauki.pl/articles/1964292.pdf
Data publikacji:
1997-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.62.Bf
74.72.-h
Opis:
The fragment approximation is used for the description of the layered cuprate structures. The characteristic structural features are distinguished which genetically relate all the layered cuprates. The classification scheme for the whole family of layered cuprates is analyzed in the fragment approximation and a possible extension of the scheme is discussed.
Źródło:
Acta Physica Polonica A; 1997, 92, 1; 143-146
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Oxygen Deficient YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$: Two Superconducting Phases
Autorzy:
Stankowski, J.
Ślązak, A.
Kempiński, W.
Andrzejewski, B.
Reichel, B.
Plesch, G.
Powiązania:
https://bibliotekanauki.pl/articles/2037166.pdf
Data publikacji:
2004-03
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.72.-h
74.62.Bf
74.62.-c
74.25.Nf
Opis:
A set of oxygen deficient powder and granular samples of YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$ ceramics was studied by means of thermogravimetric and magnetically modulated microwave absorption methods. Especially the last method has turned out to be a powerful method, which was used to determine the dependence of critical temperature T$\text{}_{c}$ on the oxygen parameterδ. Using these methods it has been shown that the removing of oxygen evokes the inhomogeneous oxygen distribution in the samples and a change in carrier concentration till to the loss of superconducting properties. A superconducting phase with T$\text{}_{c}$=60 K, which occurs in oxygen deficient YBa$\text{}_{2}$Cu$\text{}_{3}$O$\text{}_{7-δ}$ sample, is an unstable phase.
Źródło:
Acta Physica Polonica A; 2004, 105, 3; 287-294
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:
The Doped YBCO Superconductor Crystal Structure Simulation
Autorzy:
Kavečanský, V.
Diko, P.
Powiązania:
https://bibliotekanauki.pl/articles/1535386.pdf
Data publikacji:
2010-11
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
61.05.C-
74.62.Dh
74.72.-h
Opis:
Pinning process plays an important role in improving utility properties of $YBa_2Cu_3O_{7-δ}$ (YBCO) superconductors. As a consequence of the low coherent length, the most effective pinning centers in such type of materials should have nanometer size dimensions. An efficient way of introducing such centers can be a chemical substitution in the YBCO lattice. Computer simulation of locally distorted YBCO crystal structure due to the substitutions has been performed.
Źródło:
Acta Physica Polonica A; 2010, 118, 5; 1034-1035
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Resonant States of a Momentum-Dependent Impurity Potential in a d-Wave Superconductor
Autorzy:
Pisarski, P.
Harań, G.
Powiązania:
https://bibliotekanauki.pl/articles/1812293.pdf
Data publikacji:
2008-07
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.20.Rp
74.62.Dh
74.72.-h
Opis:
Nonmagnetic impurity on-site potential leads to the resonant states in a d-wave superconductor for the unitary scattering limit. We extend the above study to include a momentum dependence of the impurity potential and discuss the existence and number of resonant states for a tetragonal anisotropy of the scattering potential.
Źródło:
Acta Physica Polonica A; 2008, 114, 1; 153-157
0587-4246
1898-794X
Pojawia się w:
Acta Physica Polonica A
Dostawca treści:
Biblioteka Nauki
Artykuł
Tytuł:
Effects of Europium-Barium Nonstoichiometry in EBCO123 Systems on Transition and Magnetization Properties
Autorzy:
Cigáň, A.
Maňka, J.
Kopčok, M.
Polovková, J.
Jurdák, P.
Koňakovský, A.
Powiązania:
https://bibliotekanauki.pl/articles/1813614.pdf
Data publikacji:
2008-01
Wydawca:
Polska Akademia Nauk. Instytut Fizyki PAN
Tematy:
74.72.-h
74.62.Bf
74.25.Fy
74.25.Ha
Opis:
We studied the effects of Eu-Ba nonstoichiometry in two series of $Eu_{1+x}Ba_{2-x}Cu_3O_{7-δ}$ and $Eu_{1-x}Ba_{2+x}Cu_3O_{7-δ}$ samples on transition, structural, and magnetic properties. The samples with the nominal composition of 0≤x≤0.07 were synthesized by the solid-state reaction method from $Eu_2O_3,$ $BaCO_3,$ and CuO precursors and sintered at 1050°C for 72 h in flowing oxygen. All the samples show the values of critical temperature $T_c$, volume density ρ, and maximum volume magnetization $M_\text{max}$ higher than 90 K, 6.3 g $cm^{-3}$ and $10^4 Am^{-1}$, respectively, except for x = 0.07 samples. The Eu-Ba nonstoichiometry in the two series shows different effects on transport, magnetization hystereses, and intergrain properties of the samples.
Źródło:
Acta Physica Polonica A; 2008, 113, 1; 219-222
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:
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:
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 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 1-11 z 11

    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