材料期刊网

The magnetotransport behaviors of a series of rare earth manganites with the same A-site cational mean radius and different A-site ionic radii variance (A-site disorder) are investigated. It is found that the system's ground state transforms from ferromagnetic metal to cluster-glass insulator with increasing A-site disorder. In the cluster-glass state, the magnetization shows the steplike behavior, indicating the existence of short-range magnetically ordered clusters. The significant effect of the A-site disorder on the electronic phase separation is revealed by detecting the cluster-glass ground state at low temperature. (c) 2006 American Institute of Physics.