Eur. Phys. J. B 44, 277-280 (2005)
https://doi.org/10.1140/epjb/e2005-00126-3

Temperature-dependent scaling of pinning force data in Bi-based high-T_c superconductors

¹ University of Saarbrücken, Department of Experimental Physics, P.O. Box 15 11 50, 66041 Saarbrücken, Germany
² Electrotechnical Institute, Ulica Pozaryskiego 28, 04-703 Warszawa, Poland

Corresponding author: ^a m.koblischka@mx.uni-saarland.de

Received: 9 July 2004
Revised: 15 February 2005
Published online: 28 April 2005

Abstract

The scaling of the normalized volume pinning forces, , versus a reduced field has proven to be a very informative tool to study the origin of the flux pinning in superconductors. Remarkably, on Bi₂Sr₂Ca₂Cu₃O (Bi-2223) and Bi₂Sr₂CaCu₂O (Bi-2212) data were mostly analyzed only in a narrow temperature range around 77 K. Here, we present a study of the pinning forces in various Bi-2223 samples at temperatures between 18 K and 80 K. The measurements clearly reveal that there is an apparent non-scaling of the pinning force data; instead, two clearly different temperature regimes for the scaling can be recognized, which are found to be in direct relation to a second step observed in the m(T) curves obtained upon field-cooling and -warming.