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arXiv · 2006.01443

Optical visualization of the enhanced spin Hall effect in bismuth doped silicon

Taiki Nishijima·Yakun Liu·Dushyant Kumar·Kyusup Lee·Fabien Rortais·Syuta Honda·Yuichiro Ando·Ei Shigematsu·Ryo Ohshima·Hyunsoo Yang·Masashi Shiraishi
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Abstract

Direct visualizations of spin accumulation due to the enhanced spin Hall effect (SHE) in bismuth (Bi) - doped silicon (Si) at room temperature are realized by using helicity-dependent photovoltage (HDP) measurements. Under application of a dc current to the Bi-doped Si, clear helicity-dependent photovoltages are detected at the edges of the Si channel, indicating a perpendicular spin accumulation due to the SHE. In contrast, the HDP signals are negligibly small for phosphorus-doped Si. Compared to a platinum channel, which has a large spin Hall angle, more than two-orders of magnitude larger HDP signals are obtained in the Bi-doped Si.

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Taiki Nishijima, Yakun Liu, Dushyant Kumar, Kyusup Lee, Fabien Rortais, Syuta Honda, Yuichiro Ando, Ei Shigematsu, Ryo Ohshima, Hyunsoo Yang, Masashi Shiraishi. 2020-06-02. Optical visualization of the enhanced spin Hall effect in bismuth doped silicon. https://arxiv.org/abs/2006.01443

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