Au/PdSe ₂ /Graphene-Based Anisotropic Two-Dimensional Heterojunction for Near-Infrared Polarization Photoelectric Synapse

Anisotropic two-dimensional materials, with their unique physical properties, not only provide a critical material foundation for high-performance polarization-sensitive photoelectric synapses but also offer a feasible approach to miniaturized integrated polarization detection. However, most existing research on photoresponse focuses on the visible light band, and studies on the influencing factors and regulatory methods of photocurrents in polarized synaptic systems remain relatively limited. In this work, we successfully realized polarization-sensitive synaptic functionality in the near-infrared regime by constructing a Au/PdSe₂/graphene heterostructure. This heterojunction exhibits a maximum polarization ratio of 6.5 at a wavelength of 2200 nm and achieves an ultralow energy consumption of 1.48 pJ. Moreover, the polarization ratio can be systematically tuned by the optical power density, exhibiting a variation from 4.9 to 6.5. This work fills the technical gap in near-infrared polarization perception and provides valuable insights for optimizing the polarization detection performance of high dynamic range optoelectronic devices by investigating the regulatory mechanisms of polarized photocurrents.