Strain-induced topological phase transition in two-dimensional platinum ditelluride
arXiv:2106.16212
Abstract
Topological phase transition is a hot topic in condensed matter physics and computational material science. Here, we investigate the electronic structure and phonon dispersion of the two-dimensional (2D) platinum ditelluride () using the density functional theory. It is found that the monolayer is a trivial insulator with an indirect band gap of 0.347eV. Based on parity analysis, the biaxial tensile strain can drive the topological phase transition. As the strain reaches 19.3%, undergoes a topological phase transition, which changes from a trivial band insulator to a topological insulator with . Unlike conventional honeycomb 2D materials with topological phase transition, which gap closes at K points, the strained monolayer becomes gapless at M points under critical biaxial strain. The band inversion leads the switch of the parities near the Fermi level, which gives rise to the topological phase transition. The novel monolayer has a potential application in the field of micro-electronics.
12 pages, 6 figures