A Mixed-Dimensional van der Waals Heterostructure Photodetector

摘要： Van der Waals (vdW) heterostructures, integrated two-dimensional (2D) materials with variously functional materials, provide a distinctive platform for next-generation optoelectronics with unique flexibility and high performance. However, exploring the vdW heterostructures combined with strongly correlated electronic materials is hitherto rare. Herein, a novel temperature-sensitive photodetector based on the GaSe/VO2 mixed-dimensional vdW heterostructure is discovered. Compared with previous devices, our photodetector exhibits excellently enhanced performance, with external quantum efficiency up to 109.6 % and the highest responsivity (358.1 mA?W?1) under a 405 nm laser. Interestingly, we show that the heterostructure overcomes the limitation of a single material under the interaction between VO2 with GaSe, where photoresponse is highly sensitive to temperature and can be further shut at the critical value. The metal-insulator transition of VO2, which controls the peculiar band-structure evolution across the heterointerface, is demonstrated to manipulate the photoresponse variation. This study enables us to elucidate the method of manipulating 2D materials by strongly correlated electronic materials, paving the way for developing the high-performance and special optoelectronic application.