Electric field tunable electronic properties of P-ZnO and SiC-ZnO van der Waals heterostructures

The vertical stacking and influence of external electric field are good techniques to tune the electronic properties of two-dimensional materials for potential nanoelectronics and optoelectronic devices. The structural and electronic properties of P-ZnO and SiC-ZnO van der Waals (vdW) heterostructures are investigated by first principles calculations. P-ZnO (SiC-ZnO) heterostructure exhibits an indirect type-I (direct type-II) semiconducting band character. The effect of perpendicular applied external electric field on the electronic properties of the most stable vdW heterostructure has also been systematically discussed. Remarkable variations in the band gap nature are induced by increasing field strength from 0.1 to 1.0 V/Å (for P-ZnO) and 0.1 to 0.8 V/Å (for SiC-ZnO). The intrinsic indirect type-I is modulated to type-II semiconducting band gap in P-ZnO by applying electric field strength 0.1 V/Å. More interestingly, reduction in the size with transition from an indirect-to-direct type-II semiconductor band gap nature is noted at 0.5 V/Å. However, a direct type-II semiconductor to metallic character is found at 1.0 V/Å (for P-ZnO) and 0.8 V/Å (for SiC-ZnO). Our results suggests that these vdW heterostructures are promising candidates for electronic and optoelectronic device applications. © 2019