Study of the structural stability and electronic structure of Ce-related defects in diamonds

Abstract

Based on the first-principle method of density functional theory (DFT), the parameters of the CeV (general term for Ce-related defects) color center of diamonds are optimized and calculated using Vienna Ab-initio Simulation package software in this study. The structure of the diamond CeV2 color center is the most stable when the Ce atom is located at the substitution site with the presence of two vacancies nearby. The electronic structure of the diamond CeV2 color center is calculated on the basis of this stable structure, and the charge transfer between Ce and C atoms is determined. The energy band structure and the density of states verify that the impurity states in the band are mainly composed of the 5d and 4f orbitals of Ce atoms. The ground state of the color center of the diamond CeV2 is located in the 4f orbit, and the excited state is in the 5d orbit. The zero phonon line of the color center of the diamond CeV2 is predicted to be 2.528 eV, and the corresponding fluorescence wavelength is 490.82 nm. This can provide a theoretical basis for preparing the diamond CeV color center for subsequent experiments.