The effect of substitution of Fe with Cr on the giant magnetoresistance of current-perpendicular-to-plane spin valves with Co2FeSi Heusler alloy

作者：Goripati H S; Furubayashi T; Karthik S V; Nakatani T M; Takahashi Y K; Hono K^*

来源：Journal of Applied Physics, 2011, 109(4): 043901.

DOI：10.1063/1.3549722

We fabricated current-perpendicular-to-plane spin valves (SV) using Co2FeSi and Co-2(Cr0.1Fe0.9)Si Heusler alloys as ferromagnetic layers and a Ag spacer. The SV with Co-2(Cr0.1Fe0.9)Si showed relatively large magnetoresistance (MR) ratio of 11.9% and the resistance change-area product (Delta RA) of 6.3 m Omega mu m(2) at room temperature as compared to the MR ratio of 9.4% and the Delta RA value of 4.1 m Omega mu m(2) for the SV using Co2FeSi. This indicates that the spin polarization of Co2FeSi is enhanced by the substitution of Cr for Fe as suggested by a previous point contact Andreev reflection measurements. Considering the high Curie temperature of 993 K, the Co-2(Cr0.1Fe0.9)Si alloy could be promising material for spin polarized electron source.

• 出版日期2011-2-15