Noma Taishi, Chen Hsiao-Yi, Dhara Barun, Sotome Masato, Nomoto Takuya, Arita Ryotaro, Nakamura Masao, Miyajima Daigo
Center for Emergent Matter Science (CEMS), RIKEN, 2-1 Hirosawa, Wako, Saitama, 351-0198, Japan.
Department of Materials Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo, 113-8656, Japan.
Angew Chem Int Ed Engl. 2023 Oct 16;62(42):e202309055. doi: 10.1002/anie.202309055. Epub 2023 Sep 12.
The origin of the bulk photovoltaic effect (BPVE) was considered as a built-in electric field formed by the macroscopic polarization of materials. Alternatively, the "shift current mechanism" has been gradually accepted as the more appropriate description of the BPVE. This mechanism implies that the photocurrent generated by the BPVE is a topological current featuring an ultrafast response and dissipation-less nature, which is very attractive for photodetector applications. Meanwhile, the origin of the BPVE in organic-inorganic hybrid perovskites (OIHPs) has not been discussed and is still widely accepted as the classical mechanism without any experimental evidence. Herein, we observed the BPVE along the nonpolar axis in OIHPs, which is inconsistent with the classical explanation. Furthermore, based on the nonlinear optical tensor correlation, we substantiated that the BPVE in OIHPs is originated in the shift current mechanism.
体光伏效应（BPVE）的起源曾被认为是由材料的宏观极化形成的内建电场。另外，“位移电流机制”已逐渐被接受为对BPVE更合适的描述。该机制意味着由BPVE产生的光电流是一种具有超快响应和无耗散特性的拓扑电流，这对于光探测器应用非常有吸引力。同时，有机-无机杂化钙钛矿（OIHPs）中BPVE的起源尚未得到讨论，并且仍然被广泛接受为经典机制，却没有任何实验证据。在此，我们观察到OIHPs中沿非极性轴的BPVE，这与经典解释不一致。此外，基于非线性光学张量相关性，我们证实了OIHPs中的BPVE起源于位移电流机制。
