上海科技大学知识管理系统

In recent years, polarization infrared detection technology has made great progress and has been
successfully applied in various fields such as national defense, astronomy, and civil applications.
However, so far, the integration of micro polarizers and infrared photodetectors is still a big
challenge since metal microstructures are severely limited in their size. As anisotropic
two-dimensional (2D) materials rapidly appear, this distinctive polarization characteristic
regardless of the size provides new freedom to polarization infrared photodetectors. In this
paper, a van der Walls heterojunction with the unilateral depletion region was constructed to
obtain polarization-sensitive infrared photodetection, in which black phosphorus (BP) serves as
a natural polarizer. BP/PtS2 infrared photodetectors possess a fast response speed (the rise time
is 56 μs and the fall time is 64 μs). At the same time, these photovoltaic detectors achieve a high
detectivity of 4.47 × 1010 cm Hz1/2 W−1 at 830 nm. Using the anisotropic structure of BP, the
photovoltaic polarization detector was realized, and its polarization extinction ratio at 830 nm
was 2.66 (3.18 @ 1310 nm and 2.63 @ 1550 nm). This work discovers the potential value of
anisotropic 2D materials in infrared polarization-sensitive photodetection.