Ferroelectric‐Switchable Single Photodetector Implementing Complex Optoelectronic Logics

Abstract Optoelectronic logic gates (OELGs) are promising building blocks of edge extraction, image recognition, and data encryption in logic circuits. However, implementing complex OELGs based on CMOS devices needs additional circuit configuration due to the fixed photodetection mode, which inevitably makes the manufacturing process of chip complicated and large. This work proposes a ferroelectric‐switchable photodetector (FeS‐PD) in 2D α‐In₂Se₃/WSe₂ heterojunction, which can implement the complex OELG functions. The FeS‐PD exhibits the ferroelectric‐tunability between the photovoltaic and photoconductive mode via the sign and amplitude of polarization voltage, as well as accompanied by a high current photo/dark ratio. Moreover, the non‐volatile‐tunability of photovoltaic voltage (opening circuit voltage) distinctively enables the bias one input of logics, which enables a single device to implement the complex XOR and AND logic functions via programming gate pulse voltage, light input, and bias. Compared to the traditional CMOS‐based logic gate, FeS‐PD significantly reduces the transistor number by 91.7% and 50% for nonlinear XOR and linear AND logics, respectively. The research provides a simple platform for on‐chip optoelectronic‐logic computing circuits.