Electron Spin Resonance Shift and Linewidth Broadening of Nitrogen-Vacancy Centers in Diamond as a Function of Electron Irradiation Dose

TL;DR

This study investigates how electron irradiation affects the optical and spin properties of nitrogen-vacancy centers in diamond, revealing shifts in resonance frequency, linewidth broadening, and optimal magnetic sensitivity at low doses.

Contribution

It provides new insights into the dose-dependent behavior of NV centers' properties under electron irradiation, highlighting the impact on magnetic sensing performance.

Findings

Resonance frequency shifts up to 0.6% with increased dose

Linewidth broadens as irradiation dose increases

Magnetic sensitivity is highest at the lowest irradiation dose

Abstract

A high-nitrogen-concentration diamond sample was subject to 200-keV electron irradiation using a transmission electron microscope. The optical and spin-resonance properties of the nitrogen-vacancy (NV) color centers were investigated as a function of the irradiation dose up to 6.4\times1021 e-/cm2. The microwave transition frequency of the NV- center was found to shift by up to 0.6% (17.1 MHz) and the linewidth broadened with increasing electron-irradiation dose. Unexpectedly, the measured magnetic sensitivity is best at the lowest irradiation dose, even though the NV concentration increases monotonically with increasing dose. This is in large part due to a sharp reduction in optically-detected spin contrast at higher doses.