Microscale Sensing with Strongly Interacting NV Ensembles at High Fields

TL;DR

This paper introduces a method to improve microscale NMR sensing using highly doped NV ensembles in diamond at high magnetic fields, effectively suppressing dipole interactions to boost sensitivity.

Contribution

It presents a novel technique for high-field NMR detection with strongly interacting NV ensembles, overcoming dipole-dipole interaction challenges.

Findings

Enhanced sensitivity in high-field NMR using highly doped diamond NV ensembles.

Effective suppression of dipole-dipole interactions among NV centers.

Compatibility with increased NV concentration for improved sensing.

Abstract

Advances in sensing devices that utilize nitrogen-vacancy (NV) center ensembles in diamond are driving progress in microscale nuclear magnetic resonance spectroscopy. Utilizing quantum sensing techniques in the high-field regime significantly boosts sensitivity by increasing thermal polarization and improves spectral quality via enhanced energy shifts. Compatible with the latter, a straightforward manner to further raise sensor sensitivity is to increase NV concentration, although this intensifies detrimental dipole-dipole interactions among NVs. In this Letter, we present a method for detecting NMR signals in high-field scenarios while effectively suppressing dipole-dipole couplings in the NV ensemble. Thus, this approach enhances sensitivity by combining highly doped diamond substrates and elevated magnetic fields.