Table of Contents Author Guidelines Submit a Manuscript
Advances in Condensed Matter Physics
Volume 2013, Article ID 931726, 7 pages
http://dx.doi.org/10.1155/2013/931726
Research Article

Aging Effect on Electrical Conductivity of Pure and Al-Doped YBa2Cu3O7−δ Single Crystals with a Given Topology of Planar Defects

1Physical Department, Kharkiv National University, Kharkiv 61077, Ukraine
2Physikalisches Institut, Goethe-University, 60438 Frankfurt am Main, Germany

Received 18 August 2013; Accepted 25 September 2013

Academic Editor: Hechang Lei

Copyright © 2013 Ruslan V. Vovk et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

The conducting properties in the basal plane of pure and Al-doped single crystals before and after long-time exposure in air atmosphere are investigated. It is shown that prolonged aging leads to an increase of the density of effective scattering centers for the normal carriers. The aluminum doping has been revealed to partially slowdown the degradation of the conducting properties in process of aging. The excess conductivity, , has been found to obey exponential dependence in the broad temperature range . In the pseudogap regime, the mean-field transition temperature and the 3D-2D crossover point in the excess conductivity have been quantified. Near the critical temperature, is described well within the Aslamazov-Larkin theoretical model. Herewith, both aluminum doping and prolonged aging have been found to essentially expand the temperature interval of implementation of the pseudogap state, thus narrowing the linear section in the dependence .