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JournalISSN: 0921-4534

Physica C-superconductivity and Its Applications 

Elsevier BV
About: Physica C-superconductivity and Its Applications is an academic journal published by Elsevier BV. The journal publishes majorly in the area(s): Superconductivity & Magnetization. It has an ISSN identifier of 0921-4534. Over the lifetime, 26267 publications have been published receiving 279609 citations. The journal is also known as: Physica. C, Superconductivity and its applications.


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Journal ArticleDOI
TL;DR: In this article, the authors report the characterization of series of oxygen deficient Ba2YCu3Ox samples for 7 ≥ x ≥ 6 prepared by Zr gettered annealing at 440°C.
Abstract: We report the characterization of series of oxygen deficient Ba2YCu3Ox samples for 7 ≥ x ≥ 6 prepared by Zr gettered annealing at 440°C. Measurements include complete crystal structure analysis at 5 K by powder neutron diffraction, electron microscopy study of the oxygen ordering, and magnetic measurements of the superconducting transitions, with particular attention to the transition widths. The results show for the first time that the 90 K and 60 K plateaus in Tc as a function of oxygen stoichiometry are associated with plateaus in the effective valence of the plane coppers. We also correlate the disappearance of superconductivity for x

884 citations

Journal ArticleDOI
TL;DR: In this paper, annealing results for several Tl-superconductors in the series Tlm(Ba, Sr)2Can−1CunO2n+m+2+δ, for both m=1 and 2, revealing two general results for this class of Bi or TI superconductors: (1) effects on Tc due to labile oxygen occur for all m=2 compounds but are absent in m = 1 compounds with Sr.
Abstract: We have previously shown that Tc for Bi2 (Sr, Ca)n+1CunO2n+4+δ (n=1, 2 and 3) varies with oxygen stoichiometry δ determined by annealing in a variety of oxygen partial pressures and temperatures. Annealing results are now also presented for several Tl-superconductors in the series Tlm(Ba, Sr)2Can−1CunO2n+m+2+δ, for both m=1 and 2, revealing two general results for this class of Bi or TI superconductors: (1) effects on Tc due to labile oxygen occur for all m=2 compounds but are absent in m = 1 compounds with Sr. m=1 compounds with Ba do have variable oxygen but the effects on the c-axis are the opposite to m=2 compounds. This suggests for the latter that the labile oxygen resides in interstitial sites within the Bi2O2 or Tl2O2 bi layers; (2) the hole concentration per Cu decreases in progressing from n = 1 to 2 to 3 in either class so that the parent n = 3 and n = 2 compounds lie respectively on the low- and high-hole concentration sides of the peak in Tc while the n = 1 compounds extend out into the non-superconducting domain at very high hole concentration.

712 citations

Journal ArticleDOI
TL;DR: In this paper, the authors examined the temperature dependence of the NMR Knight shift and relaxation rate, entropy, resistivity, infrared conductivity, Raman scattering, ARPES and tunnelling data and concluded that the second scenario is not at all supported.
Abstract: Underdoped high- T c superconductors are frequently characterised by a temperature, T * , below which the normal-state pseudogap opens. Two different “phase diagrams” based on the doping ( p ) dependence of T * are currently considered: one where T * falls to zero at a critical doping state and the other where T * merges with T c in the overdoped region. By examining the temperature dependence of the NMR Knight shift and relaxation rate, entropy, resistivity, infrared conductivity, Raman scattering, ARPES and tunnelling data, it is concluded that the second scenario is not at all supported. Neither can one distinguish a small and a large pseudogap as is often done. T * is an energy scale, which falls abruptly to zero at p =0.19. Colour figures are available at cond-mat/0005063.

548 citations

Journal ArticleDOI
TL;DR: In this article, a simple theoretical model for the granularity is introduced and then used to discuss a number of electrodynamic properties (hysteretic magnetization versus magnetic field, zero-field-cooled and field cooled magnetisation versus temperature, ac susceptibility, and flux creep with logarithmic time dependence).
Abstract: The microstructure of bulk samples of the copper-oxide high-temperature superconductors commonly is describable in terms of anisotropic grains of stoichiometric material separated by layers of nonstoichiometric interface material. The granularity strongly influences the electromagnetic properties, especially the transport critical-current density and the magnetization. In this paper, a simple theoretical model for the granularity is introduced and then used to discuss a number of electrodynamic properties (hysteretic magnetization versus magnetic field, zero-field-cooled and field-cooled magnetization versus temperature, ac susceptibility, and flux creep with logarithmic time dependence). Special attention is drawn to the importance of distinguishing between intragranular and intergranular effects.

539 citations

Journal ArticleDOI
TL;DR: In this article, it was shown that there is a strong tendency for dilute holes in an antiferromagnet to phase separate, leading to high-temperature superconductivity.
Abstract: There is a strong tendency for dilute holes in an antiferromagnet to phase separate. (This is a generic feature of doping into a commensurate correlated insulating state.) We review the general and model-specific theoretical arguments that support this conclusion for neutral holes. In the presence of long-range Coulomb interactions, there is frustrated phase separation leading to large-amplitude, low-energy fluctuations in the hole density at intermediate length scales, provided the dielectric constant is sufficiently large. We describe extensive experimental evidence showing that such “clumping” of the holes is an important feature of the cuprate superconductors. We also summarize theoretical results which suggest that frustrated phase separation may account for the anomalous properties of the normal state and give rise to high-temperature superconductivity.

506 citations

Performance
Metrics
No. of papers from the Journal in previous years
YearPapers
202336
202263
2021114
2020118
2019133
2018192