Regulation of electronic structures in ReSeS monolayer with anisotropic deformations

Because of their unique and rich physical properties, transition metal dichalcogenides (TMDs) materials have attracted much interest. Many studies suggest that introducing the degree of freedom of anisotropy—which may be brought about by low structural symmetry—might further optimize their applications in industry and manufacturing. However, most currently reported TMDs do not achieve the theoretical minimum symmetry. Utilizing the first principles calculation, we present ReSeS monolayer with a Janus structure. Results indicate that its electronic dispersion is sensitive to structural distortions, which increases metallicity. Our reduction-Hamiltonian can provide a qualitative description, but further analyses reveal that bonding/antibonding properties near the Fermi surface are the more fundamental cause of the variations. Furthermore, geometric deformations can regulate the effective mass of electrons as well as the spectroscopic response, resulting in anisotropic behaviours. Our ideas serve as a foundation for developing new regulable optoelectronic devices.