Electronic Structure of Wurtzite Ga<sub>0.75</sub>Al<sub>0.25</sub>N: A First Principle Calculation

Abstract

In order to lay theoretical foundations for preparation of Ga0.75Al0.25N photocathodes, research on ternary Ш-V alloys Ga0.75Al0.25N are carried on. Using CASTEP software package based on density functional theory within a plane wave ultrasoft pseudo potential scheme, total energies, band structures, density of states, and charge distribution of three different structures of wurtzite Ga0.75Al0.25N are calculated. Results show that the structure in which Al atoms in para-positon of interlayer is most stable. Ga0.75Al0.25N is semiconductor with direct band gap. The threshold wavelength is 321.8nm which can satisfy the need of preparation of “solar blind” photocathodes.