Optical Properties of (100), (110), and (111) SnTe Slabs: Effects of Surface Termination and Electric Field

We investigate the optical properties of SnTe slabs with (100), (110), and (111) orientations using a tight-binding approach that incorporates the effects of surface termination and an external electric field. Each surface orientation exhibits distinct electronic structures that strongly influence the interband transition spectra. The application of an out-of-plane electric field breaks inversion symmetry and induces charge redistribution across the slabs, leading to tunable band gaps and anisotropic optical responses. These findings demonstrate how crystallographic orientation, surface termination, and an external electric field can be controlled to engineer the electronic and optical characteristics of SnTe for optoelectronic applications.