nanoTesla magnetometry with the silicon vacancy in silicon carbide

TL;DR

This paper demonstrates nanoTesla sensitivity magnetometry using silicon vacancies in silicon carbide, achieving high sensitivity with simple, low-power optical techniques, highlighting its potential for cost-effective quantum magnetic sensing.

Contribution

The study reports the first realization of nanoTesla-level magnetometry with silicon vacancies in silicon carbide using simple optical detection without complex photonic structures.

Findings

Achieved 3.5 nT/√Hz sensitivity.

No complex photonic engineering or high-power excitation needed.

Demonstrated cost-effective quantum magnetic sensing.

Abstract

Silicon Carbide is a promising host material for spin defect based quantum sensors owing to its commercial availability and established techniques for electrical and optical microfabricated device integration. The negatively charged silicon vacancy is one of the leading spin defects studied in silicon carbide owing to its near telecom photoemission, high spin number, and nearly temperature independent ground state zero field splitting. We report the realization of nanoTesla shot-noise limited ensemble magnetometry based on optically detected magnetic resonance with the silicon vacancy in 4H silicon carbide. By coarsely optimizing the anneal parameters and minimizing power broadening, we achieved a sensitivity of 3.5 nT/$\sqrt{Hz}$. This was accomplished without utilizing complex photonic engineering, control protocols, or applying excitation powers greater than a Watt. This work demonstrates that the silicon vacancy in silicon carbide provides a low-cost and simple approach to quantum sensing of magnetic fields.