Advances in 2D Linear‐Polarization‐Sensitive Optoelectronic Synapses: From Anisotropic Carrier Dynamics to Neuromorphic Polarized Vision

ABSTRACT Integrating polarization discrimination directly into optoelectronic synapses enables the fusion of polarization perception, memory, and preprocessing at the device level, thereby enhancing information density and computational efficiency. This architecture overcomes the limitations of conventional polarization detection schemes that rely on bulky optical components and external data processing. Two‐dimensional (2D) materials provide a versatile platform for such on‐chip linear‐polarization‐sensitive optoelectronic synapses (LPOSs), owing to their tunable anisotropy and heterointegration compatibility. This review systematically surveys recent advances in 2D LPOSs through three material design strategies: intrinsic low‐symmetry crystals, heterostructure engineering, and artificially induced anisotropy. We establish a comparative framework correlating crystal symmetry, polarization‐selective absorption, carrier dynamics, and synaptic plasticity via four key mechanisms: defect‐dominated carrier trapping, strain‐bulk photovoltaic (strain‐BPV)‐assisted carrier separation, intrinsic slow carrier relaxation, and heterojunction‐mediated charge storage. We further highlight emerging applications in polarization‐encoded optical communication, bioinspired navigation, and in‐sensor imaging. Finally, we discuss critical challenges and outline future directions toward strongly anisotropic materials, actively tunable polarization sensitivity, and wafer‐scale integration, offering a roadmap for high‐performance LPOSs and compact neuromorphic polarized visual systems.