Title :
Critical currents and thermal activation in a-axis oriented EuBa/sub 2/Cu/sub 3/O/sub 7/ thin films
Author :
Velez, M. ; Martin, J.I. ; Vicent, J.L.
Author_Institution :
Dept. de Fisica de Mater., Univ. Complutense de Madrid, Spain
fDate :
6/1/1995 12:00:00 AM
Abstract :
a-axis oriented EuBa/sub 2/Cu/sub 3/O/sub 7//SrTiO/sub 3/(100) thin films have been grown by DC magnetron sputtering. Critical current and resistivity have been measured as a function of temperature, down to 15 K, and field, up to 9 T. In spite of the existence of 90/spl deg/ grain boundaries, the critical current is not limited by weak links. The lower part of the resistivity transition and the field dependence of the pinning force may be understood in terms of thermally activated flux creep with activation energy U(T,H)=U/sub 0/(T)/H and U/sub 0/ values of several hundreds of meV.<>
Keywords :
Josephson effect; barium compounds; critical currents; electrical resistivity; europium compounds; flux creep; flux pinning; grain boundaries; high-temperature superconductors; sputtered coatings; superconducting thin films; superconducting transition temperature; 0 to 9 T; 15 to 300 K; DC magnetron sputtering; EuBa/sub 2/Cu/sub 3/O/sub 7/; EuBa/sub 2/Cu/sub 3/O/sub 7/ thin films; critical current; field dependence; grain boundaries; pinning force; resistivity; resistivity transitions; temperature dependence; thermally activated flux creep; weak links; Conductivity; Critical current; Current measurement; Grain boundaries; Magnetic field measurement; Magnetic flux; Sputtering; Temperature; Thermal force; Thermal resistance;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
