Self-interaction correction calculations of band edges and alignments in low-dimensional transition metal chalcogenides and their heterostructure

In view of realizing advanced devices based on newly emerging low-dimensional materials and their heterostructures, prediction of band edges and their alignment is currently a primary target of first-principles calculations. Because of the self-interaction error, the conventional LDA and GGA within density functional theory (DFT) perform poorly in predicting band lineup and defect states. Although adopting hybrid DFT functionals or the many-body GW method could be in principle a solution, their computational cost is too high to be routinely employed. Self-interaction correction approaches could provide a practical solution for this problem, and we particularly consider the atomic self-interaction correction (ASIC) method [1]. While previous ASIC studies typically used a globally fixed ASIC parameter (α), we recently showed that selecting different α according to atomic species could provide more reliable defect level locations for transition metal dichalcogenide (TMDC)/graphene interfaces [2]. Here, we extend the study and apply the method to various TMDC/TMDC and TMDC/graphene heterostructures, as well as low-dimensional Cd and Zn chalcogenides.
[1] C. D. Pemmaraju, et al. Phys. Rev. B 75, 045101 (2007).
[2] J. Shim, et al. Adva. Mater. 28, 5293 (2016).