[10a-N305-1~10] CS.8 Code-sharing Session of 4.5 & 17

▲ [10a-N305-2] Bulk photovoltaic effect in WSe₂/Black Phosphorus interfaces

〇Toshiya Ideue¹, Takatoshi Akamatsu¹, Zhou Ling², Yu Dong¹, Sota Kitamura¹, Mao Yoshii¹, Dongyang Yang³, Masaru Onga¹, Yuji Nakagawa¹, Kenji Watanabe⁴, Takashi Taniguchi⁴, Joseph Laurienzo⁵, Junwei Huang², Ziliang Ye³, Takahiro Morimoto¹, Hongtao Yuan², Yoshihiro Iwasa^1,6 (1.The Univ. of Tokyo, 2.Nanjing Univ., 3.The Univ. of British Columbia, 4.NIMS, 5.Case Western Reserve Univ., 6.RIKEN CEMS)

Keywords:van der Waals heterointerface, bulk photovoltaic effect, shift current

We studied the van der Waals interface composed of two-dimensional crystals with different symmetries (three-fold rotational WSe₂ and two-fold rotational black phosphorus (BP)). Because three-fold rotational symmetry and two-fold rotational symmetry cannot be compatible, interface of WSe₂ and BP has no rotational symmetry and only one mirror plane exists if the mirror planes of both WSe₂ and BP are parallel. As a result, in-plane electronic polarization can emerge, which cause the bulk photovoltaic effect along the polar direction. The observed photocurrent responses can be well explained by a quantum-mechanical shift current. The present results offer a simple guideline for symmetry engineering applicable to a variety of van der Waals nanostructures and also provide the concept of electronic polarization in quasi-periodic systems.