Nitrogen-Vacancy Color Centers Created by Proton Implantation in a Diamond

Abstract

We present an experimental study of the longitudinal and transverse relaxation of ensembles of negatively charged nitrogen-vacancy (NV${}^{-}$) centers in a diamond monocrystal prepared by 1.8 MeV proton implantation. The focused proton beam was used to introduce vacancies at a 20 µ$\mathsf{\mu }$m depth layer. Applied doses were in the range of $1.5\times {10}^{13}$ to $1.5\times {10}^{17}$ ions/cm${}^2$. The samples were subsequently annealed in vacuum which resulted in a migration of vacancies and their association with the nitrogen present in the diamond matrix. The proton implantation technique proved versatile to control production of nitrogen-vacancy color centers in thin films.