skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Fast vortex motion and filamentary phase separation in high-T{sub c} thin films.

Abstract

We investigated the temperature dependence of the normalized logarithmic relaxation rate S(T) and the corresponding temperature dependence of the critical current I{sub c}(T) in high-T{sub c} thin films (YBCO-123, TlBCCO-2212, -2223, and -2201, and Bi-2212). Experiments have been performed using persistent critical currents flowing in the a-b planes of ring-shaped samples. The magnitude of Ic and the relaxation rate have been extracted from the measurement of the self-field of the current. The results revealed a relationship between I{sub c}(T) and S(T). I{sub c}(T) in YBCO is a superposition of two universal components: an underdoped Ginzburg-Landau- (GL-) like one with I{sub c}(T){sup {infinity}}(T{sub c}-T){sup 3/2} and T{sub c} between 40 and 60 K, and an Ambegaokar-Baratoff-like one close to an optimum doping. The results revealed that when the amount of the GL-like phase increases above a certain threshold value, a peak appears in S(T) at temperatures of 20-30 K, and its height gradually increases with the magnitude of I{sub c} at 10 K for this phase. We discuss similarities between these results and those reported for YBCO crystals with columnar defects. The presence of two maxima in S(T) have been observed for TlBCCO films that are composed of three different phases,more » at temperatures close to T{sub c} of two underdoped components. The studies imply that the filamentary phase separation on a nanometer scale level in the a-b planes is responsible for the changes in vortex dynamics.« less

Authors:
; ; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC); FOR
OSTI Identifier:
943147
Report Number(s):
ANL/MSD/JA-37831
Journal ID: ISSN 1098-0121; TRN: US201002%%630
DOE Contract Number:  
DE-AC02-06CH11357
Resource Type:
Journal Article
Journal Name:
Phys. Rev. B
Additional Journal Information:
Journal Volume: 61; Journal Issue: 17 ; May 1, 2000; Journal ID: ISSN 1098-0121
Country of Publication:
United States
Language:
ENGLISH
Subject:
75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY; BARIUM OXIDES; CALCIUM OXIDES; COPPER OXIDES; CRITICAL CURRENT; CRYSTALS; DEFECTS; DYNAMICS; FILMS; HEIGHT; HIGH-TC SUPERCONDUCTORS; LEVELS; MOTION; RELAXATION; TEMPERATURE DEPENDENCE; THALLIUM OXIDES; THIN FILMS; YTTRIUM OXIDES

Citation Formats

Yan, H., Jung, J., Darhmaoui, H., Ren, Z. F., Wang, J. H., Kwok, W. K., Materials Science Division, Univ. of Alberta, and State Univ. of New York at Buffalo. Fast vortex motion and filamentary phase separation in high-T{sub c} thin films.. United States: N. p., 2000. Web. doi:10.1103/PhysRevB.61.11711.
Yan, H., Jung, J., Darhmaoui, H., Ren, Z. F., Wang, J. H., Kwok, W. K., Materials Science Division, Univ. of Alberta, & State Univ. of New York at Buffalo. Fast vortex motion and filamentary phase separation in high-T{sub c} thin films.. United States. doi:10.1103/PhysRevB.61.11711.
Yan, H., Jung, J., Darhmaoui, H., Ren, Z. F., Wang, J. H., Kwok, W. K., Materials Science Division, Univ. of Alberta, and State Univ. of New York at Buffalo. Mon . "Fast vortex motion and filamentary phase separation in high-T{sub c} thin films.". United States. doi:10.1103/PhysRevB.61.11711.
@article{osti_943147,
title = {Fast vortex motion and filamentary phase separation in high-T{sub c} thin films.},
author = {Yan, H. and Jung, J. and Darhmaoui, H. and Ren, Z. F. and Wang, J. H. and Kwok, W. K. and Materials Science Division and Univ. of Alberta and State Univ. of New York at Buffalo},
abstractNote = {We investigated the temperature dependence of the normalized logarithmic relaxation rate S(T) and the corresponding temperature dependence of the critical current I{sub c}(T) in high-T{sub c} thin films (YBCO-123, TlBCCO-2212, -2223, and -2201, and Bi-2212). Experiments have been performed using persistent critical currents flowing in the a-b planes of ring-shaped samples. The magnitude of Ic and the relaxation rate have been extracted from the measurement of the self-field of the current. The results revealed a relationship between I{sub c}(T) and S(T). I{sub c}(T) in YBCO is a superposition of two universal components: an underdoped Ginzburg-Landau- (GL-) like one with I{sub c}(T){sup {infinity}}(T{sub c}-T){sup 3/2} and T{sub c} between 40 and 60 K, and an Ambegaokar-Baratoff-like one close to an optimum doping. The results revealed that when the amount of the GL-like phase increases above a certain threshold value, a peak appears in S(T) at temperatures of 20-30 K, and its height gradually increases with the magnitude of I{sub c} at 10 K for this phase. We discuss similarities between these results and those reported for YBCO crystals with columnar defects. The presence of two maxima in S(T) have been observed for TlBCCO films that are composed of three different phases, at temperatures close to T{sub c} of two underdoped components. The studies imply that the filamentary phase separation on a nanometer scale level in the a-b planes is responsible for the changes in vortex dynamics.},
doi = {10.1103/PhysRevB.61.11711},
journal = {Phys. Rev. B},
issn = {1098-0121},
number = 17 ; May 1, 2000,
volume = 61,
place = {United States},
year = {2000},
month = {5}
}