First-principles study of X/Bi2Te3(0001) surface (X = Ag, Ni, Ti).

The influence of Ag, Ni and Ti on the electronic properties of Bi2Te3 has been analysed. The relaxation of clean Bi2Te3(0001) surface and relaxation of silver, nickel and titanium on clean Bi2Te3(0001) surface have been studied using ab-initio density-functional techniques. STM images of surface, the total density of states and the band structure of bismuth telluride were determined by using the Quantum-Espresso ab-initio simulation package based on pseudopotential method. The relaxation was performed on a 8x8x1 k-point mesh, whereas in the calculations of the density of states the 12x12x1 k-point mesh was used. [ABSTRACT FROM AUTHOR]