Density-functional theory study of the interaction between NV$^{-}$ centers and native defects in diamond

TL;DR

This study uses density-functional theory to analyze how native defects in diamond influence the quantum properties of NV$^{-}$ centers, which are crucial for nanoscale sensing applications, revealing the spatial extent of defect effects.

Contribution

It combines quantum embedding and density-functional theory to quantify native defect impacts on NV$^{-}$ centers, providing a multiscale model for defect influence on quantum sensing.

Findings

Native defects affect NV$^{-}$ optical properties up to 200 nm away.

Charged native defects influence NV$^{-}$ within 1 micron.

Measuring multiple NV$^{-}$ centers can identify defect types and charge states.

Abstract

The NV$^{-}$ color center in diamond has been demonstrated as a nanoscale sensor for quantum metrology. However, the properties that make it ideal for measuring, e.g., minute electric and magnetic fields also make it sensitive to imperfections in the diamond host. In this work, we quantify the impact of nearby native defects on the many-body states of NV$^{-}$. We combine previous quantum embedding results of strain and electric-field susceptibilities of NV$^{-}$ with density-functional theory calculations on native defects. The latter are used to parametrize continuum models in order to extrapolate the effects of native defects up to the micrometer scale. We show that under ideal measuring conditions, the optical properties of NV$^{-}$ are measurably affected by the strain caused by single carbon interstitials and vacancies up to 200 nm away; in contrast, the NV$^{-}$ is measurably affected by the electric field of such charged (neutral) native defects within a micron (100 nm). Finally, we show how measuring multiple individual NV$^{-}$ centers in the vicinity of a native defect can be used to determine the nature of the defect and its charge state.