Spin convertance at magnetic interfaces

The exchange interaction between the conduction electrons and magnetic moments at magnetic interface leads to mutual conversion between electron spin current and magnon current. We introduce a concept of spin convertance which quantitatively measures the magnon current induced by electron spin accumulation and the spin current created by magnon accumulation at the interface. We predict the phenomena on charge and spin drag across a magnetic insulator spacer for several layered structures.Comment: 16 pages, 4 figures; Eq.(9) modifie