Magnetic relaxation and irreversibility in a superconducting Tl₂Ba₂Ca₂Cu₃O_10±x thin film

Authors

V.K. Chan, University of Nebraska - Lincoln
Sy_Hwang Liou, University of Nebraska-LincolnFollow

Date of this Version

March 1992

Comments

Published by American Physical Society. Phys. Rev. B45, 5547(1992). http://prb.aps.org. Copyright © 1992 American Physical Society. Permission to use.

Abstract

The magnetic relaxation in a Tl₂Ba₂Ca₂Cu₃O_10±x superconducting thin film has been measured at a range of temperatures (5–70 K) and field strengths (500–5000 Oe). Measurements reveal that the relaxation obeys a logarithmic time dependence in the time interval 2000 s<t<12 000 s. The relaxation rate is both temperature and field dependent. The average pinning potential U* calculated from the relationship U*=kT/[(-1/M_i)dM/d lnt] is in the range 20–70 meV, which is similar to those of Y-Ba-Cu-O and (Bi,Pb)-Sr-Ca-Cu-O. The anomalous increase of U* at higher temperature is found to be closely related to the irreversibility line.