Electronic and optical properties of monolayer InSe quantum dots

mobility have attracted increasing research interest. In this work, we demonstrate theoretically the strong geometry confinement in InSe quantum dots (QD) and manipulate their electronic and optical properties using QD shape and external field. The electronic energy levels, density of states, probability density of states and magneto-optical absorption spectra, are calculated by utilizing the tight-binding (TB) method with coulomb interaction in Hubbard model. In contrast to other 2D materials, e.g., phosphorene, InSe-QDs exhibit distinct features as (1) edge states appear in the bottom of the conduction band regardless of the shapes of InSe-QDs. (2) The edge states are mainly provided by the In atoms at the both armchair and zigzag edges in InSe-QDs. (3) Optical gap is distinct from band gap. The rectangular InSe-QDs produce anisotropic optical absorption spectra, whereas hexagonal and triangular InSe-QDs produce isotropic absorption spectra. The applied magnetic field would weaken this anisotropy.