Interplay of growth mode and thermally induced spin accumulation in epitaxial Al/Co2TiSi/Al and Al/Co2TiGe/Al contacts

Article

关键词: HEUSLER ALLOYS;    THERMOELECTRIC-POWER;    GE;    AL;    PSEUDOPOTENTIALS;    TRANSPORT;    INJECTION;    ALUMINUM;    COBALT;    METAL;   

DOI  :  10.1103/PhysRevB.89.184422

来源: SCIE

【 摘 要 】

The feasibility of thermally driven spin injectors built from half-metallic Heusler alloys inserted between Al leads was investigated by means of ab initio calculations of the thermodynamic stability and electronic transport. We have focused on two main issues and found that (i) the interface between Al and the closely lattice-matched Heusler alloys of type Co(2)TiZ (Z = Si or Ge) is stable under various growth conditions; and (ii) the conventional and spin-dependent Seebeck coefficients in such heterojunctions exhibit a strong dependence on both the spacer and the atomic composition of the Al/Heusler interface. The latter quantity gives a measure of the spin accumulation and varies between +8 and -3 mu V/K near 300 K, depending on whether a Ti-Ge or a Co-Co plane makes the contact between Al and Co2TiGe in the trilayer. Our results show that it is in principle possible to tailor the spin-caloric effects by a targeted growth control of the samples.

【 授权许可】

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