Ta₂NiSe₅/MoTe₂/Graphene van der Waals Heterostructures Toward Ultrabroadband and Polarization-Sensitive Imaging

Ultrabroadband and polarization-sensitive imaging are essential for pioneering advancements in intelligent technology, offering a pivotal pathway to multidimensional information extraction. However, the dearth of appropriate photosensitive semiconductors in the infrared region and the lack of suitably efficient device architecture for the separation and collection of photocarriers significantly impede the development of ultra-broadband and polarization-sensitive photodetectors. To address these challenges, a sandwiched Ta2NiSe5/MoTe2/Graphene heterostructure device is engineered. In this device, efficient and polarization-sensitive photocarriers are generated in the top Ta2NiSe5 layer, rapidly separated through the middle MoTe2 layer, and effectively collected by the bottom graphene layer. As a result, the developed photodetector exhibits an ultra-broadband and polarization-sensitive photoresponse that extends from visible light (520 nm) to short-wave infrared (2200 nm). At 2200 nm, the device displays a notable responsivity of 5.79 A W-1, a specific detectivity of 10(10) Jones, and an anisotropic ratio of 1.44. Furthermore, this device successfully demonstrates high-resolution ultra-broadband and polarized light imaging capabilities. This study thus presents an intriguing blueprint for the development of advanced 2D imaging platforms for future-generation intelligent systems.