Self‐Powered Circularly Polarized Photodetectors Based on Chiral (R/S‐MBA)2PbI4 Perovskite

Abstract Circularly polarized light (CPL) detection has extensive applications in the fields of optoelectronic devices, information security, biomedical imaging, and so on. Due to their unique structure, the (R)‐(+)‐α‐methylbenzylamine (R‐MBA) and (S)‐(−)‐α‐methylbenzylamine (S‐MBA) are chosen as a chiral cationic template. The chiral 2D perovskite (R/S‐MBA) 2 PbI 4 single crystals exhibit high absorption and prominent circular dichroism (CD) signals, highlighting their significant potential for CPL detectors. In this study, a self‐powered (R/S‐MBA) 2 PbI 4 circularly polarized photodetector is reported. The responsivity (R), specific detectivity (D * ), and light on/off ratio of the (R‐MBA) 2 PbI 4 device under 532 nm right‐handed circularly polarized (RCP) light at 0 V bias voltage are 58 mA W −1 , 2.96 × 10 11 Jones, and 568. These values of the (S‐MBA) 2 PbI 4 device are 61 mA W −1 , 3.09 × 10 11 Jones, and 478 under left‐handed circularly polarized (LCP) light at 0 V bias voltage. The photocurrent anisotropy factor (g Iph ) for (R‐MBA) 2 PbI 4 and (S‐MBA) 2 PbI 4 is exhibited to be 0.03 and 0.05, demonstrating a strong selectivity for CPL. The biomimetic CPL imaging system, bio‐inspired by mantis shrimp vision, further provides its practical potential in high‐resolution polarization‐sensitive applications. The research offers a solution for next‐generation CPL detection technologies.