Principle study of structure, energetics, and electrical properties of Ge-N-vacancy complexes in diamond

Abstract

Following first principles and inspired by the special structure of the nickel–nitrogen color center, this work enhances the known diamond germanium-vacancy (GeV) color center by adding nitrogen (N) atoms and increasing the number of vacancies. Results demonstrate that the most stable structure is one without vacancies, where the germanium (Ge) atoms are connected to four N atoms. This work analyzes the new structure of the GeV color center and determines the charge transfer and bonding from the difference in charge density. The electron bands and density of states of the GeV color center with four N atoms are calculated. By analyzing the electrical properties of each atom, we posit that the N atom is a transitional modified atom. The new structure of the GeV color center has good prospects for use in sensors and single-photon sources.