Efficient Avalanche Photodiodes with a WSe2/MoS2 Heterostructure via Two-Photon Absorption

• DOI: 10.1021/acs.nanolett.2c03629
• Publication Date: 2022-11-23T01:52:01Z
• Authors: Bongkwon Son; Yadong Wang; Manlin Luo; Kunze Lu; Youngmin Kim; Hyo-Jun Joo; Yu Yi; Chongwu Wang; Qi Jie Wang; Sang Hoon Chae; Donguk Nam
• Keywords: Photodetection; Photodiode

Two-dimensional (2D) materials-based photodetectors in the infrared range hold key to enabling a wide of optoelectronics applications including imaging and optical communications. While there exist 2D materials with narrow bandgap sensitive photons, two-photon absorption (TPA) process can also enable photodetection well-established large bandgaps such as WSe2 MoS2. However, most TPA suffer from low responsivity, preventing this method being widely adopted for photodetection. Herein, we experimentally demonstrate avalanche photodiodes achieving an ultrahigh responsivity. The WSe2/MoS2 heterostructure absorbs photons energy smaller than material via low-efficiency process. significant effect gain ∼1300 improves resulting record-high responsivity 88 μA/W. We believe that work paves way toward building practical high-efficiency photodetectors.