A Cu‐Doping Strategy to Enhance Photoelectric Performance of Self‐Powered Hole‐Conductor‐Free Perovskite Photodetector for Optical Communication Applications

Abstract Photodetectors are essential parts of wireless optical communication system for obtaining high fidelity signal transmission, which mainly relies on expensive and energy‐consuming Si, GaN, and InGaAs based photodiodes. The emerging organic–inorganic metal halide perovskite materials, with the merits of low‐cost, strong optical absorption, superior charge transport, and so on, are widely investigated in photodetection applications. Herein, a Cu ion induced p‐type doping strategy for perovskite film is proposed to facilitate hole transport, passivate trap states, avoid charge accumulation, and suppress recombination of photogenerated carriers, contributing to an enhanced photoelectric performance for self‐powered hole‐conductor‐free devices. The optimal device shows a highest responsivity of 0.37 A W⁻¹, detectivity of 1.06 × 10¹² Jones, linear dynamic range of over 101 dB, and an ultimate photoresponse rate approaching 5 µs. Moreover, an optical communication system integrated with the perovskite photodetector as light signal receiver for transmitting digital signals is demonstrated, in which characters can be transmitted accurately, and audio signal is recovered with high fidelity. The results suggest that with proper chemical modification, perovskite materials are promising alternative to inorganic semiconductors for efficient photodetection in advanced integrated optical communication system.