Structural, elastic, electronic, and anisotropic properties of Pbca-SiC and Pbcn-SiC

Abstract

The crystal structures, mechanical stability, anisotropy, electronic band structures, and effective mass of Pbca-SiC and Pbcn-SiC under pressure are calculated utilizing first-principles calculations. Pbca-SiC and Pbcn-SiC with pressures in the range of 0–50 GPa have thermodynamic and mechanical stability. Visible anisotropies are discovered by analyzing the two- and three-dimensional representations of Young’s modulus, which also change with increasing pressure. The band structure results forecast two wide bandgap semiconductors. Pbca-SiC is an indirect gap semiconductor with a value of 3.724 eV. It is worth noting that Pbcn-SiC is a direct gap semiconductor with a value of 3.639 eV, and the bandgaps of Pbcn-SiC decrease with increasing pressure, which makes the emission wavelength of Pbcn-SiC change from the near ultraviolet light zone to visible light zone. Based on the controllable direct bandgap, Pbcn-SiC has better application potential in light-emitting devices. Moreover, the carrier effective mass under ambient conditions is also calculated, and the minimum value of the electron effective mass is obtained in Pbcn-SiC with a value of 0.262m0, while the minimum value of the hole effective mass is found in Pbca-SiC with a value of −0.285m0.