Electronic structure and optical properties of As-rich reconstruction phases of Ga0.5Al0.5As (100): A first-principles research

Four As-rich reconstruction models: alpha(2x4), beta 1(2x4), beta 2(2x4) and gamma(2x4) phases are built, using first-principles method, electrical structure and optical properties of these four phases are researched. Results show that beta 2(2x4) is the most easily formed reconstructed phase. Sp3 hybrid orbital is changed when the reconstructed phases are formed. The electron transition from VBM to CBM of alpha(2x4) is the easiest while the photoemission of gamma(2x4) phase is easiest. During the formtion of the phases, the metal reflection characteristic region moves towards the lower energy end and the energy range of the metal reflection characteristic region becomes smaller. beta 2 (2x4) phase is the most favorable to the transmission of photons.