Nanoscale Electric Field Imaging with an Ambient Scanning Quantum Sensor Microscope

TL;DR

This paper demonstrates ambient-condition nanoscale electric field imaging using a single NV center at a diamond tip, achieving high sensitivity and resolution, advancing quantum sensing capabilities.

Contribution

It introduces a scanning NV electrometry technique for external AC and DC electric fields with high sensitivity and sub-100 nm resolution under ambient conditions.

Findings

Achieved 26 mV/μm/Hz^{1/2} AC electric field sensitivity.

Achieved 2 V/μm^2/Hz^{1/2} DC electric field gradient sensitivity.

Demonstrated imaging of electric fields with sub-100 nm resolution.

Abstract

Nitrogen-vacancy (NV) center in diamond is a promising quantum sensor with remarkably versatile sensing capabilities. While scanning NV magnetometry is well-established, NV electrometry has been so far limited to bulk diamonds. Here we demonstrate imaging external alternating (AC) and direct (DC) electric fields with a single NV at the apex of a diamond scanning tip under ambient conditions. A strong electric field screening effect is observed at low frequencies due to charge noise on the surface. We quantitatively measure its frequency dependence, and overcome this screening by mechanically oscillating the tip for imaging DC fields. Our scanning NV electrometry achieved an AC E-field sensitivity of 26 mV um^(-1) Hz^(-1/2), a DC E-field gradient sensitivity of 2 V um^(-2) Hz^(-1/2), and sub-100 nm resolution limited by the NV-sample distance. Our work represents an important step toward building a scanning-probe-based multimodal quantum sensing platform.