标题：Giant Two-Photon Absorption in Mixed Halide Perovskite CH3NH3Pb0.75Sn0.25I3 Thin Films and Application to Photodetection at Optical Communication Wavelengths
作者：Xie, Ying; Fan, Jiandong; Liu, Chong; Chi, Shumeng; Wang, Zeyan; Yu, Haohai; Zhang, Huaijin; Mai, Yaohua; Wang, Jiyang
作者机构：[Xie, Ying; Chi, Shumeng; Wang, Zeyan; Yu, Haohai; Zhang, Huaijin; Wang, Jiyang] Shandong Univ, State Key Lab Crystal Mat, Jinan 250100, Shandong, Peo 更多
通讯作者：Yu, HH;Zhang, HJ;Yu, HH;Zhang, HJ
通讯作者地址：[Yu, HH; Zhang, HJ]Shandong Univ, State Key Lab Crystal Mat, Jinan 250100, Shandong, Peoples R China;[Yu, HH; Zhang, HJ]Shandong Univ, Inst Crystal Ma 更多
来源：ADVANCED OPTICAL MATERIALS
关键词：metal halide perovskites; nonlinear optical response; photodetection;; thin films
摘要：Photodetection in the optical communication wavelength band (OCWB) is a key technique for data processing communications. Photodetectors with integrability, ease of fabrication, low cost, and excellent detection properties are favorable for practical applications. Metal halide perovskite thin films have exhibited intriguing optoelectronic properties. However, their relatively wide intrinsic band gaps indicate that direct photodetection in the infrared OCWB seems impossible. Here, for the first time, direct infrared photodetection covering the OCWB with a metal halide perovskite is demonstrated. Associated with an Sn-component dependent band gap, a CH3NH3Pb0.75Sn0.25I3 perovskite thin film is fabricated, whose nonlinear two-photon absorption can expand the optical response up to 1.8 mu m. Two-photon absorption is studied and a very large absorption coefficient of 1.15 cm kW(-1) is measured, a value that is respectively 5 and 10(6) times larger than that of CH3NH3PbI3 thin films and halide perovskite bulk crystals. Based on this favorable performance, direct photodetection at 1535 nm in the C-band of the OCWB and at 1064 nm is characterized. The realization of direct infrared photodetection in a metal halide perovskite provides a possible alternative in advanced integrated optoelectronics and electronics.