Theoretical investigation of (GaAs)n/(InAs)n (n=1,2,3) superlattice structures

In this thesis, we investigated that the structural and lattice dynamical properties of the (GaAs)n/(InAs)n (n=1,2,3) superlattices by using the most popular ab initio method which is very useful to understand the properties of materials and which too many scientists work on it last years. The calculations have been carried out by using the density-functional and density-functional perturbation theory with in the local density approximation using norm conserving and optimized pseudopotentials and a plane-wave basis. At the first step of our calculations optimization procedures were held for GaAs and InAs structures and then these results were compared with available data from the literature. After seeing our calculation results were in good agreement with literature data calculations for bandstructure, density of states, phonon dispersion curves and phonon density of states curves were done. After these, calculations for (GaAs)n/(InAs)n (n=1,2,3) superlattices were done and we saw that our calculations are in good aggrement with available data from the literature.