Inverse design of non-uniformly distributed square GaAs nanowire array solar absorbers

Abstract

The non-uniformly distributed square GaAs nanowire array solar absorbers are inversely designed using the Particle Swarm Optimization algorithm to maximum photoelectric conversion efficiency. The absorption spectra of optimized structures with fixed volume and fixed length all show a flatter trend attributed to the superposition of absorption peaks with different spacing nanowires, and are significantly increased at long wavelengths due to the enhanced trapping effect. The fixed-volume and fixed-length array have diversified distributions, resulting in a performance improvement with remarkable short-circuit current density of 30.80 mA/cm² and 31.29 mA/cm² and ultimate efficiency of 33.97% and 34.51%, respectively. In addition, the absorptance exceeds 90% across the wide band range of 300–830 nm. This study provides a novel concept for the design of high-performance nanowire array solar photoelectric devices.