Spin pumping efficiency from half metallic CoMnSi

Chudo, Hiroyuki ; Ando, Kazuya*; Saito, Kesami*; Okayasu, Satoru  ; Haruki, Rie; Sakuraba, Yuya*; Yasuoka, Hiroshi; Takanashi, Koki; Saito, Eiji

We present spin pumping using a Heusler alloy CoMnSi/Pt bilayer film. A spin current is produced by a ferromagnetic resonance (FMR) technique. The pure spin current injected into the Pt layer from the CoMnSi layer is detected by the inverse spin-Hall effect (ISHE), which converts the spin current into an electric current. We estimated a damping constant of the CoMnSi/Pt bilayer film from an angular dependence of FMR spectra. Using the damping constant efficiency of spin pumping from the CoMnSi layer is evaluated. We found that a mixing conductance at the CoMnSi/Pt interface is comparable to that at a permalloy/Pt interface.