Electronic and optical properties of arsenic monolayers

Group-V monolayer materials exhibit intriguing electronic and optical properties, influenced by their unique crystal symmetries and structural phases. In this work, we explore arsenic monolayers, investigating their electronic and structural properties across different phases, including planar, buckled, and puckered forms, using density functional theory (DFT) and quasi-particle self-consistent GW (QSGW) methods, with and without vertex contributions (ladder diagrams). We also examine the gradual transformation between these phases and its impact on the band structure. Additionally, recognizing the importance of excitonic effects in 2D materials, we employ the Bethe-Salpeter equation (BSE) method to study the optical response.