Disordering effects in the atomic structure of fine-crystalline HTSC YBa2Cu3Oy

被引：16

作者：

Balagurov, A. M. ^{[1
]}

Mamsurova, L. G. ^{[2
]}

Bobrikov, I. A. ^{[1
]}

To Thanh Loan ^{[1
]}

Pomjakushin, V. Yu. ^{[3
]}

Pigalskiy, K. S. ^{[2
]}

Trusevich, N. G. ^{[2
]}

Vishnev, A. A. ^{[2
]}

机构：

[1] Joint Inst Nucl Res, Dubna 141980, Russia

[2] Russian Acad Sci, NN Semenov Chem Phys Inst, Moscow 119991, Russia

[3] Paul Scherrer Inst, Neutron Scattering Lab, CH-5232 Villigen, Switzerland

来源：

JOURNAL OF EXPERIMENTAL AND THEORETICAL PHYSICS | 2012年 / 114卷 / 06期

基金：

俄罗斯基础研究基金会;

关键词：

NEUTRON POWDER DIFFRACTION; REVERSIBLE MAGNETIZATION; COMPARATIVE MOSSBAUER; GRAINED HTSC; SUPERCONDUCTORS; OXYGEN; TC; YBACUO;

D O I：

10.1134/S106377611204005X

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

The atomic structure of YBa2Cu3O (y) fine-crystalline HTSC samples with various average crystallite sizes aOE (c) D > ranging from 0.4 to 2 mu m and an oxygen concentration y close to the optimal value for superconductivity (y a parts per thousand 6.93) is investigated by the neutron diffraction technique. We have found some effects associated with the redistribution of cations and oxygen atoms and with variations in the positions of atomic layers in the unit cell, which are not observed in macrocrystalline samples. In all probability, these effects appear due to nonequilibrium conditions of synthesis required for obtaining this compound in the fine-crystalline state. The results have made it possible to explain the peculiar physical properties of fine-crystalline YBa2Cu3O (y) samples (in particular, the coexistence of high superconducting transition temperatures T (c) and noticeably lower values of magnetization in strong magnetic fields for T < T (c) ). It is shown that a nanoscale structural inhomogeneity exists in fine-crystalline YBa2Cu3O (y) samples with the optimal oxygen content and changes the fundamental superconducting parameters, viz., the magnetic field penetration depth and the coherence length.

引用

页码：1001 / 1011

页数：11

共 26 条

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