Paramagnetic properties of NdFeAsO0.91F0.06 polycrystals

Abstract

The temperature and field dependencies of magnetization of NdFeAsO 0.94F0.06 bulk sample are shown to exhibit the Curie-Weiss behaviour, both in the superconducting and normal states. To address the origin of the strong paramagnetic signal, particularly to reveal contributions from antiferromagnetic second phases in sintered NdFeAsO0.94F 0.06, the magnetic response of Nd2O3 was measured and compared with NdFeAsO0.94F0.06. Our measurements show that paramagnetism of NdFeAsO0.94F0.06 is an intrinsic property dominated by Nd3+ ions contribution, which cannot be explained by magnetic second phases. ©2008 The Physical Society of Japan.