Impact of Photoelectric Readout Noise on Magnetic Field Sensitivity of NV Centers in Diamond

TL;DR

This paper analyzes how photoelectric readout noise affects the magnetic field sensitivity of NV centers in diamond, showing potential for significantly improved on-chip magnetometers.

Contribution

It provides a quantitative analysis of photoelectric readout noise and demonstrates its potential to outperform optical readout in magnetic sensing.

Findings

Photoelectric readout noise can be modeled with Gaussian statistics.

Johnson-Nyquist noise limits the photoelectric magnetic field sensitivity.

Photoelectric detection could outperform optical methods by an order of magnitude.

Abstract

Nitrogen-vacancy (NV) centers in diamond are of great interest for nano- and macro-scale magnetic field sensing. Most sensing protocols rely on conventional optical readout, which is limited by photon shot noise. The recently developed photoelectrical (PE) readout of the NV center electron spin state promises to overcome these limitations. However, the noise of the PE readout and its influence on readout efficiency have not been thoroughly studied. In this work, we perform magnetic field sensing and estimate the sensitivity using optical and PE readout with a single and an ensemble of NV centers in diamond. We investigate the electronic noise associated with the photoelectric detection and estimate the readout efficiency, using Gaussian statistics. Our quantitative analysis shows that the Johnson-Nyquist noise-limited photoelectric magnetic field sensitivity could outperform optical measurements by an order of magnitude. This work is an essential step towards the development of on-chip magnetometers using photoelectrical detection in diamond.