We employ plane-wave with ultrasoft pseudopotential method to calculate and compare the total density of states and partial density of states of bulk-phase GaN, Ga0:9375N, and GaN0:9375 systems based on the first-principle density-functional theory (DFT). For Ga and N vacancies, the electronic structures of their neighbor and next-neighbor atoms change partially. The Ga0:9375N system has n-type semiconductor conductive properties, whereas the GaN0:9375 system has p-type semiconductor conductive properties. By studying the optical properties, the influence of Ga and N vacancy defects on the optical properties of GaN has been shown as mainly in the low-energy area and very weak in high-energy area. The dielectric peak influenced by vacancy defects expands to the visible light area, which greatly increases the electronic transition in visible light area.
© 2012 Chinese Optics Letters
Yujie Du, Benkang Chang, Honggang Wang, Junju Zhang, and Meishan Wang, "First principle study of the influence of vacancy defects on optical properties of GaN," Chin. Opt. Lett. 10, 051601- (2012)