A Review of Electronic Structure Tuning in Bi₂Se₃ Topological Insulators

Abstract

Motivated by the discovery of quantum spin Hall systems, topological insulators constitute a class of quantum phase with insulating bulk and symmetry-protected metallic boundary modes, arising from nontrivial band topology. Among them, Bi2Se3 and its related substances are gradually known as the representative three-dimensional strong topology analyzer because of their large bulk energy gap, a Dirac cone on the surface and good chemical stability. In ideal theory, topological surface states have linear dispersion and anti-nonmagnetic scattering properties, so they are attractive in both basic research and application. However, in real materials, inherent defects will produce a lot of bulk carrier, which will lead to the increase of bulk conductivity, and it is difficult to see the contribution of “surface states” in transportation measurement. In order to solve this problem, various methods to adjust the electronic structure of Bi2Se3 are proposed. This review summarizes the latest progress of Bi2Se3 topology installers in electronic structure adjustment. We will focus on nonmagnetic doping and strain engineering in particular, and briefly discuss other methods, including electric-field control and interface engineering. By comparing various adjustment methods, we will explain their advantages and limitations, and expound the direction and prospect of better electronic control in the future.