[22a-B201-1~11] 10.1 新物質・新機能創成（作製・評価技術）

▲ [22a-B201-11] Prediction of half-metallic gap formation and Fermi level position in Co-based Heusler alloy epitaxial thin films through anisotropic magnetoresistance effect

〇(P)Varun Kumar Kushwaha¹、S. Kokado²、S. Kasai¹、Y. Miura¹、T. Nakatani¹、R. Kumara³、H. Tajiri³、T. Furubayashi¹、K. Hono¹、Y. Sakuraba¹ (1.NIMS、2.Shizuoka Univ.、3.JASRI)

キーワード：Spintronics materials, Heusler alloys, Half-metallic ferromagnets

To deepen the understanding of a relationship between anisotropic magnetoresistance (AMR) and half-metallic electronic structure, we have investigated the temperature (T) dependence of the AMR effect of Co₂FeGa_0.5Ge_0.5 (CFGG) epitaxial thin films having different compositions and atomic orders. It was found that the T dependence of resistance-change (Δρ) of the AMR normalized at 10 K is minimum in the CFGG films having a standard composition and high atomic order. In contrast, the CFGG films with a high disorder always exhibit a large reduction of Δρ with T. Our developed theoretical model of AMR well explains such tendency in the T dependence of Δρ. The present study proves that the formation of a half-metallic gap and the position of Fermi level (E_F) in a half-metallic material are readily predictable from the T dependence of Δρ of the AMR effect, which can be a facile way for efficient screening of half-metallic materials.