Analysis of electronical properties of Bismuth and Silicene antidot in the presence of strain using the four-orbital tight-binding method

Abstract

We have performed a tight-binding calculation of the band structure of Bi/Si sheets on which hexagonal holes are embedded. We named this kind of structure as Bismuth/Silicene antidot lattice (BAL/SAL). We have considered the semi-empirical sp3 tight-binding model on which the nearest and next-nearest neighbors of atoms have been taken into account. Our numerical results show that the size of holes in the two-dimensional sheets as the antidot lattice points are effective on the band structures and also transport properties of the system. Also, we have observed that BALs are almost conductors with very small band gaps for the large radius of circles, but about SALs for the large radius of holes, we obtain a considerable band gap, and conductivity is reduced. Besides, we have seen that, for the different radius of holes in the monolayer of Silicene, the presence of spin-orbit coupling in our band gaps obtained by tight-binding is not very important. On the contrary to Silicene antidot lattice, SOC interaction has a considerable effect on the band gap for Bismuth antidot lattice for the various radiuses of holes in their monolayer. Also, we have investigated the effects of the distance between holes on BAL/SAL band gaps and their band structures. Finally, we have obtained the band gap of Bismuth/Silicene antidot under strain, and we have compared results of sheet and antidot in the presence of strain.