Uncooled near- to long-wave-infrared polarization-sensitive photodetectors based on MoSe2/PdSe2 van der Waals heterostructures

Infrared polarization-sensitive photodetectors have attracted considerable interest for night vision, remote sensing and imaging applications. Traditional bulk infrared photodetectors suffer from integration challenges and high-power consumption induced by the cryogenic cooling requirement. Here, we demonstrate a tunneling-dominant triple-junction broadband polarization-sensitive photodetector based on a van der Waals heterostructure, operating from the near-infrared (NIR) to the long-wave infrared (LWIR) band. The device exhibits low noise current, low power consumption and high detectivity. Benefiting from the photogating-assisted tunneling, it reaches a responsivity of ~ 8 × 104 A/W and a response speed of 590 ns under NIR illumination. Apparent blackbody response and high photoresponse up to 10.6 μm is achieved with a room temperature responsivity and detectivity of 0.47 A/W and over 109 Jones. Remarkably, bias-tunable polarization detection capability and high polarization ratios are observed from NIR to LWIR, which further boost target detection and imaging capabilities. Our results offer a promising approach for multidimensional imaging applications and device miniaturization. Conventional bulk infrared detectors usually operate at cryogenic temperatures, leading to high power consumption. Here, the authors report high-performance polarization-sensitive photodetectors based on MoSe2/PdSe2 heterostructures, operating from the near- to the long-wave infrared band at room temperature.