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arXiv · 1810.06879

Quantitative and systematic analysis of bias dependence of spin accumulation voltage in a non-degenerate Si spin valve

Soobeom Lee·Fabien Rortais·Ryo Ohshima·Yuichiro Ando·Shinji Miwa·Yoshishige Suzuki·Hayato Koike·Masashi Shiraishi
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Abstract

Spin accumulation voltages in a non-degenerate Si spin valve are discussed quantitatively as a function of electric bias current using systematic experiments and model calculations. As an open question in semiconductor spintronics, the origin of the deviation of spin accumulation voltages measured experimentally in a non-degenerate Si spin valve is clarified from that obtained by model calculation using the spin drift diffusion equation including the effect of the spin-dependent interfacial resistance of tunneling barriers. Unlike the case of metallic spin valves, the bias dependence of the resistance-area product for a ferromagnet/MgO/Si interface, resulting in the reappearance of the conductance mismatch, plays a central role to induce the deviation.

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Soobeom Lee, Fabien Rortais, Ryo Ohshima, Yuichiro Ando, Shinji Miwa, Yoshishige Suzuki, Hayato Koike, Masashi Shiraishi. 2018-10-16. Quantitative and systematic analysis of bias dependence of spin accumulation voltage in a non-degenerate Si spin valve. https://doi.org/10.1103/physrevb.99.064408

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