Creation of Depth-Confined, Shallow Nitrogen-Vacancy Centers in Diamond With Tunable Density

TL;DR

This paper presents a method for creating shallow nitrogen-vacancy centers in diamond with tunable density using delta doping during growth, improving control over NV placement and enabling advanced quantum sensing applications.

Contribution

It introduces a delta doping technique for precise control of NV depth and density, surpassing traditional ion implantation methods.

Findings

Achieved twofold improvement in NV depth confinement.

Demonstrated imaging of magnetism in 2D material CrSBr.

Produced highly-sensitive NV ensembles with coherence limited by NV-NV interactions.

Abstract

Engineering shallow nitrogen-vacancy (NV) centers in diamond holds the key to unlocking new advances in nanoscale quantum sensing. We find that the creation of near-surface NVs through delta doping during diamond growth allows for tunable control over both NV depth confinement (with a twofold improvement relative to low-energy ion implantation) and NV density, ultimately resulting in highly-sensitive single defects and ensembles with coherence limited by NV-NV interactions. Additionally, we demonstrate the utility of our shallow delta-doped NVs by imaging magnetism in few-layer CrSBr, a two-dimensional magnet. We anticipate that the control afforded by near-surface delta doping will enable new developments in NV quantum sensing from nanoscale NMR to entanglement-enhanced metrology.