Strain-tunable electronic anisotropy of the AlSb double-layer honeycomb structure

Two-dimensional (2D) materials show promising applications in nanoelectronic devices due to their excellent physical and chemical properties, large specific surface area, and good flexibility. 2D AlSb, a representative of a new class of two-dimensional materials with a double-layer honeycomb (DLHC) structure was recently obtained in experiments and was reported to be a direct band gap semiconductor. Strain engineering is an effective way of tuning the properties of 2D materials. Here, by first-principles calculations, the strain effects on the electronic structure of AlSb were investigated. An interesting inversion of band order near the bottom of the conduction band can be induced by applying uniaxial strain, which will introduce a large electronic anisotropy. In addition, under tensile strain along the armchair direction larger than 5%, band inversion occurs, indicating possible topological insulator properties of AlSb. Small carrier effective mass and strain tunable electronic anisotropy pave the way for the application of AlSb in future nanoelectronic devices.