Optimizing the Design of the Vapor‐Deposited CsPbCl₃‐Based Optoelectronic Devices via Simulations and Experiments

Abstract Wide‐bandgap CsPbCl₃ perovskite has fueled studies on applications in a variety of newly developing optoelectronic devices, including solar cells, lasers, light‐emitting diodes, and photodetectors. Most of them are now focused on film fabrication and device performance optimization, technology transfer of these proof‐of‐concept devices to the market will necessitate optimization of the device structure to minimize the optical loss and fabrication cost. While device model‐based electro‐optics simulations are considered a powerful method to attain the purpose, during which accurate optical constants are preconditions. Herein, for the first time, the optical constants of CsPbCl₃ film through Mueller matrix spectroscopic ellipsometry (SE) are reported. Taking optoelectronic devices in vertical structure as a demonstration, simulations on the distributions of 2D electromagnetic field and photo‐generated electron field are arranged, successfully demonstrating the profile of the photons and electrons inside the devices. The evolution trend of device performance in the experiments matched with the simulations, for device performance is closely related to the photons and photo‐generated electrons. Benefitting from the simulations and experiments, general design criteria of the CsPbCl₃‐based optoelectronic and photonic devices are posed, inevitably accelerating their development and commercialization.