Calculation of semiconductor band structure based on density functional theory and many-body perturbation theory

T. T. Bazhirov, M. Kh. Salakhov

Institute of Physics, Kazan (Volga region) Federal University

Abstract: This paper describes in detail the energy band stucture calculation method for solids. The calculation results are given for three semiconductors with different bandgap values. The electronic wavefunctions and energy levels in the first approximation are obtained using density functional theory (DFT). The quasiparticle energy levels calculation mechanism is described based on the DFT results and many-body perturbation theory in the GW approximation. Energy eigenvalues inside the Brillouin zone are obtained with a state-of-the-art accuracy using high convergence parameters and Wannier interpolation. Quasiparticle states are found to have good agreement with experimental data. The advantages and limitations of the utilized approach are mentioned.

Keywords: density functional theory, GW approximation, eigenenergy, band structure, quasiparticle energy levels, electron transition, dispersion relations.

UDC: 538.915

Received: 17.05.2010