Summary of Doctoral Thesis in Phycics: Excitonic condensation in semimetal – semiconductor transition systems

Purpose: Developing mean-field theory for a 2D two-band model including electron – phonon interaction and the extended Falicov-Kimball model involving electron/hole – phonon interaction. Studying the properties of electronic systems in EI state through investigating the above models. Then, we compare the nature of each condensation state on both sides of the BCS – BEC crossover or the competition with the CDW state.