Optoelectronic and mechanical properties of monolayer bismuthene under strain modulation: Insight from first-principles calculations

Bismuthene is a promising candidate for ultrafast optics and topological applications due to its exceptional properties. In this paper, the optical, electronic, and mechanical properties of monolayer bismuthene modulated by uniaxial and biaxial strain were theoretically investigated using a first-principles approach. The results reveal that the effects of spin-orbit coupling, energy bands, transition dipole moments, and joint density of states combine to cause shifts of optical absorption peaks under strain. Bismuthene can remain stable under a wide range of strains, with the Young's modulus exhibiting consistent variations to the Poisson's ratio. Additionally, a negative Poisson's ratio of bismuthene was displayed under significant tensile strains. These findings provide insights into modulating the optoelectronic and mechanical properties of bismuthene nanomaterials to meet the demands of advanced devices and applications.