The electric and magnetic properties in granular perovskite La 0.8Sr 0.2MnO 3 have been investigated. A giant magnetoresistance (GMR) has been observed at temperatures well below T c, the Curie temperature, associated with crystal intrinsic magnetic properties. The granular GMR effect is also isotropic but shows some characteristics different from those in the films and crystals of similar perovskites. This suggests an effect of interfacial spin-dependent tunneling in the granular perovskite at temperatures much lower than T c. In addition, with the reduction of grain size, an evident superparamagnetic behavior has been observed.
ASJC Scopus subject areas
- Physics and Astronomy(all)