Role of coexistence of superconductivity and paramagnetism in magnetostriction of high-T c superconductors

Abstract

Total magnetostriction in the superconducting state for high-T c superconductors has been separated into critical state and paramagnetic components in terms of a H (x) dependent magnetic flux density. We show that the paramagnetic part is X (2+X) ?H (x) 2?, where X is paramagnetic susceptibility. We have reproduced successfully ?L/L - H a curves measured by de la Fuente et al. (Phys. C 244:214, 1995), in which they clearly observed coexistence of superconductivity and paramagnetism, employing the concepts presented in this work. © Springer Science+Business Media, LLC 2008.