Low-energy Ga2O3 polymorphs with low electron effective masses

The calculated electronic and optical properties of β-Ga2O3 based on the first principles

INTRODUCTION

The electronic and optical properties of β-Ga2O3 have been investigated by CASTEP using first principles. It is found that β-Ga2O3 has an indirect band gap and the conduction band base is located at the Γ point. The stability of β-Ga2O3 is demonstrated by the calculation of elastic constants, and the ductility of β-Ga2O3 is demonstrated by the ratio of Poisson's ratio to shear modulus. The optical property analysis shows that β-Ga2O3 has a high absorption capacity in the ultraviolet region, but a low absorption capacity in visible and infrared light.

CONTEXT

The structure, optical, and electronic properties of β-Ga2O3 are calculated and analyzed based on first-principles calculation. The optimized structures of β-Ga2O3 are in good agreement with previously studied. In this paper, the elastic, electronic, and optical properties of β-Ga2O3 are calculated.

METHODS

The CASTEP code was employed to execute these calculations in the present work, where the exchange-correlation interactions were treated in the generalized gradient approximation (GGA) using the Perdew-Burke-Ernzerhof (PBE) functional in the geometry optimizations and electronic and elastic properties.

A New BCN Compound with Monoclinic Symmetry: First-Principle Calculations

In this study, we predicted and investigated a new light-element compound B-C-N in Pm phase, denoted as Pm-BCN, using density functional theory. Pm-BCN is mechanically, dynamically, and thermodynamically stable. The elastic moduli of Pm-BCN are larger than those of other B-C-N and light-element compounds, such as P2₁3 BN, B₂C₃, P4/m BN, Pnc2 BN, and dz4 BN. By studying the mechanical anisotropy of elastic moduli, we proved that Pm-BCN is a mechanically anisotropic material. In addition, the shear anisotropy factors A₂ and A_Ba of Pm-BCN are smaller than those of the seven B-C-N compounds mentioned in this paper. Pm-BCN is a semiconductor material with an indirect and wide band gap, suggesting that Pm-BCN can be applied in microelectronic devices.