Metallic ordered double-perovskite Sr2CrReO6 with maximal Curie temperature of 635 K

Electric, thermal, optical, and magnetic properties have been investigated for ferromagnetic (ferrimagnetic) ordered double perovskites, A(2)CrReO(6) (A=Sr and Ca). Sr2CrReO6 is found to be a metallic ferromagnet with a high Curie temperature (T-C=635 K), possibly the highest-T-C half metal among the perovskite family. By contrast, Ca2CrReO6 is a ferromagnetic Mott insulator with T-C of 360 K. (C) 2002 American Institute of Physics.