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arXiv · 2203.06790

Tunable bulk photovoltaic effect in strained $\gamma$-GeSe

Hong-Guk Min·Churlhi Lyi·Youngkuk Kim
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Abstract

Recently, Lee \textit{et. al.} [Nano Lett. \textbf{21}, 4305 (2021)] newly synthesized monochalcogenide GeSe in a polar phase, referred to as $\gamma$-phase. Motivated by this work, we study shift current of $\gamma$-GeSe and its tunability via an in-plane uniaxial strain. Using first-principles calculations, we uncover the electronic structure of the strained $\gamma$-GeSe systems. We then calculate frequency-dependent shift current conductivities at various strains. The tunability is demonstrated to enhance the shift current up to $\sim$ 20 $\mu$A/V$^2$. Moreover, the direction of shift current can be inverted by a light strain. Markedly, an anomalous behavior is found in the zero-frequency limit, which can be an indicative of band inversion and a potential topological phase transition driven by the strain. Our results suggest that shift current can be a tangible prove of bulk electronic states of $\gamma$-GeSe.

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Hong-Guk Min, Churlhi Lyi, Youngkuk Kim. 2022-03-14. Tunable bulk photovoltaic effect in strained $\gamma$-GeSe. https://doi.org/10.1103/physrevb.106.205153

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