Eur. Phys. J. B 69, 161-165 (2009)
https://doi.org/10.1140/epjb/e2009-00117-4

Magnetic transition and Meissner shielding in ferromagnetic high-T_c superconductor RuSr₂Gd_1.4Ce_0.6Cu₂O_10-δ

Department of Physics, University of Science and Technology of China, Hefei, 230026, Anhui, P.R. China

Corresponding author: ^a kqruan@ustc.edu.cn

Received: 15 May 2008
Revised: 10 January 2009
Published online: 28 March 2009

Abstract

The magnetic superconductor RuSr₂Gd_1.4Ce_0.6Cu₂O_10-δ was studied by means of detailed magnetization measurements in order to clarify its complex magnetic and superconducting properties. Our experiments agree with a model indicating that the in-plane component of the Ru moment might transform from a spin-glass ground state to a ferromagnetically coupled excited state by application of a small magnetic field below the magnetic transition temperature. The experiments also show that a full Meissner state is present at the low temperature, the low magnetic field region of the phase diagram. This is in contrast to the previous prediction that no Meissner state exists in this material for an internal magnetic field of several hundred Oersteds in the CuO₂ planes exerted by the Ru sublattice and exceeding the lower critical field.