Optical properties for the oxygen vacancies in β-Ga2O3 based on first-principles calculations

Abstract

We present a comprehensive study based on first-principles calculations for three different oxygen vacancies with three different charge states (0, +1, +2) in β-Ga2O3. We adopt the well-known FNV correction scheme for the finite-size system and overcome the 'band-edge' problem by the hybrid functional (method purposed by Alkauskas). Since the luminescence band of β-Ga2O3 still remain debatable and mysterious, we put our emphases on the optical properties of the oxygen vacancies and we find a new green luminescence (GL) band through theoretical calculation and attribute it to one of the three oxygen vacancies. Besides, optical absorption for all oxygen vacancies have peaks in UV region.