Electronic structure and optical properties of the tellurium hyper-doped silicon: first-principles evaluation

The tellurium-hyper-doped silicon has been attracting increasing attention of the research community because its infrared absorption spectrum can be used for development of efficient infrared optoelectronic devices compatible with well-developed technologies. Further success in application of this material, however, requires better understanding of the relation between its excited electronic states and optical properties. In this work, we, first, perform density-functional-theory based calculations to evaluate the formation energy of substitutional TeSi doping and dynamic stability of the material with 0.8% and1.85% Te concentrations. Next, we applied the advanced linear response GW method and Bethe-Salpeter equation computational techniques to obtain accurate electronic structure and optical excitation characteristics of these materials. Finally, we provide a detailed analysis of the effect of the dopant of varying concentration on the electronic structure and absorption spectrum of the Te-doped silicon.