[10a-N305-1~10] CS.8 4.5 Nanocarbon and 2D Materials、17 ナノカーボンのコードシェアセッション

▲ [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)

キーワード：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.