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arXiv · 1601.00759

Observation of large spin accumulation voltages in non-degenerate Si spin devices due to spin drift effect: Experiments and theory

Takayuki Tahara·Yuichiro Ando·Makoto Kameno·Hayato Koike·Kazuhito Tanaka·Shinji Miwa·Yoshishige Suzuki·Tomoyuki Sasaki·Tohru Oikawa·Masashi Shiraishi
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Abstract

A large spin-accumulation voltage of more than 1.5 mV at 1 mA, i.e., a magnetoresistance of 1.5 Ω, was measured by means of the local three-terminal magnetoresistance in nondegenerate Si-based lateral spin valves (LSVs) at room temperature. This is the largest spin-accumulation voltage measured in semiconductor-based LSVs. The modified spin drift-diffusion model, which successfully accounts for the spin drift effect, explains the large spin-accumulation voltage and significant bias-current-polarity dependence. The model also shows that the spin drift effect enhances the spin-dependent magnetoresistance in the electric two terminal scheme. This finding provides a useful guiding principle for spin metal-oxide semiconductor field-effect transistor (MOSFET) operations.

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Takayuki Tahara, Yuichiro Ando, Makoto Kameno, Hayato Koike, Kazuhito Tanaka, Shinji Miwa, Yoshishige Suzuki, Tomoyuki Sasaki, Tohru Oikawa, Masashi Shiraishi. 2016-01-05. Observation of large spin accumulation voltages in non-degenerate Si spin devices due to spin drift effect: Experiments and theory. https://doi.org/10.1103/physrevb.93.214406

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