Determination of dielectric axes and transition moment directions in β-Ga2O3 from the polarization dependence of vibrational spectra

Abstract

β-Ga2O3 is a promising ultrawide bandgap semiconductor for high power and extreme environment applications. The dominant O—H center in Ga2O3 has been assigned to a Ga(1) vacancy–2H (VGa(1)-2H) complex. An analysis of the polarization dependence of the vibrational absorption of the VGa(1)-2D center in monoclinic β-Ga2O3 provides a unique strategy for the determination of both the orientation of the principal dielectric axes in the near infrared and the direction of the vibrational transition moment of the defect.