[12a-S302-1~7] 10.3 スピンデバイス・磁気メモリ・ストレージ技術

▼ [12a-S302-1] Large impact of spin-scattering asymmetry at Co₂Fe_0.4Mn_0.6Si/CoFe ferromagnetic interface on current-perpendicular-to-plane giant magnetoresistance

〇Yuichi Fujita¹、Yoshio Miura¹、Taisuke Sasaki¹、Tomoya Nakatani¹、Kazuhiro Hono¹、Yuya Sakuraba¹ (1.NIMS)

キーワード：spintronics, giant magnetoresistance, Heusler alloy

In this study, we show direct evidence for interface spin-scattering asymmetry (γ) at half metallic ferromagnet/ferromagnet interface based on a half metallic Co₂Fe_0.4Mn_0.6Si (CFMS)/CoFe interface. Fully epitaxial current-perpendicular-to-plane giant magnetoresistance (CPP-GMR) pseudo spin-valve (PSV) devices involving CoFe/CFMS/Ag/CFMS/CoFe structures exhibit an enhancement in resistance change-area product owing to the formation of the CFMS/CoFe interface at room temperature. This is well reproduced qualitatively by a simulation based on the generalized two-current series-resistor model with considering the presence of large γ at the CFMS/CoFe interface in the CPP-GMR PSV structure. We also discuss the results of the first-principles ballistic transport calculations for (001)-CoFe/CFMS/CoFe, which indicate strong spin-dependent conductance at the CFMS/CoFe interface, suggesting large γ.