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In this research, we introduce a PdSe 2 /2H-MoTe 2 heterojunction photodetector that exhibits both broadband self-powered photodetection and linear/circular polarization detection capabilities. It has a broad spectral response range (covering 375-2200 nm) and reaches a peak sensitivity at 532 nm, exhibiting a notable responsivity of 7.3 × 10 3 A/W and a substantial specific detectivity of 8.5 × 10 12 Jones. Even in the near-infrared region of 1310 nm, it still has a high responsivity of 20 A/W. The self-powered photodetection capabilities of the PdSe 2 /2H-MoTe 2 heterojunction are equally impressive, covering a broad range from 375 to 1550 nm, with a responsivity of 243 mA/W, a specific detectivity of 6.46 × 10 10 Jones, a fill factor of 0.8, and an external quantum efficiency of 56.73%. Finally, simultaneous implementation of linear/circular polarization detection on the PdSe 2 /2H-MoTe 2 heterojunction provides a powerful solution for near-infrared full-Stokes polarization detectors with high integration, miniaturization, and portability.

The optoelectronic synaptic transistors with various functions, broad spectral perception, and low power consumption are an urgent need for the development of advanced optical neural network systems. However, it remains a great challenge to realize the functional diversification of the systems on a single device. 2D van der Waals (vdW) materials can combine unique properties by stacking with each other to form heterojunctions, which may provide a strategy for solving this problem. Herein, an all-2D vdW heterojunction-based programmable optoelectronic synaptic transistor based on MoS 2 /Ta 2 NiS 5 heterojunctions is demonstrated. The device implements reconfigurable, multilevel non-volatile memory (NVM) states through sequential modulation of multiple optical and electrical stimuli to achieve broadband (532-808 nm), energy-efficient (17.2 fJ), hetero-synaptic functionality in a bionic manner. The intrinsic working mechanisms of the photogating effect caused by band alignment and the interfacial trapping defect modulation induced by gate voltage are revealed by Kelvin-probe force microscopy (KPFM) measurements and carrier transport analysis. Overall, the (opto)electronic synaptic weight controllability for combined in-sensor and in-memory logic processors is realized by the heterojunction properties. The proposed findings facilitate the technical realization of generic all 2D hetero-synapses for future artificial vision systems, opto-logical systems, and Internet of Things (IoT) entities., (© 2024 Wiley‐VCH GmbH.)