PDF study of spinel fine particle with giant magnetic coercive force

社本 真一; 松村 大樹; 山元 洋*; 田口 富嗣; 山本 博之; 西畑 保雄; Proffen, T.*; 堀石 七生*

no journal, , 

Magnetic spinel fine particle CoNiCrFeO with giant coercive force of H=1.73 T at room temperature has been studied by atomic pair distribution function analysis of pulsed-neutron diffraction data. The high coercivity decreased to 0.25 T after annealing in air at 673 K accompanied by dehydration reaction and site exchange of Co and Fe ions between A and B sites in a spinel lattice. The number of Co ions at tetrahedral A site was reduced by the dehydration reaction. The result suggests that Co ions at tetrahedral A site in a spinel lattice may play an important role for the giant coercivity.