Effect of interfacial spin mixing conductance on gyromagnetic ratio of Gd substituted Y$_{3}$Fe$_{5}$O$_{12}$

Abstract

Due to its low intrinsic damping, Y 3 Fe 5 O 12 and its substituted variations are often used for ferromagnetic layer at spin pumping experiment. Spin pumping is an interfacial spin current generation in the interface of ferromagnet and non-magnetic metal, governed by spin mixing conductance parameter ↑↓ . ↑↓ has been shown to enhance the damping of the ferromagnetic layer. The theory suggested that the effect of ↑↓ on gyromagnetic ratio only comes from its negligible imaginary part. In this article, we show that the different damping of ferrimagnetic lattices induced by ↑↓ can affect the gyromagnetic ratio of Gd-substituted Y 3 Fe 5 O 12 .