Electrically Engineered Band Gap in Two-Dimensional Ge, Sn, and Pb: A First-Principles and Tight-Binding Approach

摘要: First-principles calculations were performed to investigate the electronic structure of two-dimensional (2-D) Ge, Sn, and Pb without with presence an external electric field in combination spin-orbit coupling. Tight-binding based on four orbitals per atom effective single orbital are presented match results obtained from first-principles calculations. In particular, band splitting investigated both models. Moreover, simple $k\cdot p$ model is also considered order understand A large obtained, which expected be useful for spintronic devices. The fair agreement between first-principle, model, tight-binding approaches leads a table parameters future studies hexagonal 2-D nanostructures. By using tight binding parameters, transport properties typical 0-D triangular quantum dots two semi-infinite electrodes coupling addressed.