Photonic and electronic properties of two-dimensional GaN monolayer and AA/AA′ stacked structures: First-principles and quantum transport simulations

This paper investigates the electrical and optical properties of monolayer and bilayer gallium nitride (GaN) with different stacking configurations (AA and AA′) through first-principles calculations and quantum transport simulations. The analysis shows that the stacking arrangement significantly influences the optical and electrical properties of GaN, with the AA-stacking structure exhibiting enhanced stronger absorption coefficients and higher reflectivity. Based on these properties, a self-powered ultraviolet photodetector was designed. The AA-stacking structure demonstrates remarkable photocurrent response and excellent polarization sensitivity across a broad ultraviolet spectral range from 2 to 6.0 eV. These results suggest that tuning the stacking configuration can effectively improve the performance of photodetectors, offering new insights and strategies for the development of high-performance optoelectronic detectors in the future.