A single spin in hexagonal boron nitride for vectorial quantum magnetometry.

M Gilardoni, Carmem; Eizagirre Barker, Simone; Curtin, Catherine L; Fraser, Stephanie A; Powell, Oliver F J; Lewis, Dillon K; Deng, Xiaoxi; Ramsay, Andrew J et al. · Nat Commun · 2025

basic_science · Level V

Where this comes from

Abstract

Quantum sensing based on solid-state spin defects provides a uniquely versatile platform for nanoscale magnetometry under diverse environmental conditions. Operation of most sensors used to-date is based on projective measurement along a single axis combined with computational extrapolation. Here, we show that an individually addressable carbon-related spin defect in hexagonal boron nitride is a multi-axis nanoscale sensor with large dynamic range. For this spin-1 system, we demonstrate how its spin-dependent photodynamics give rise to three optically detected spin resonances that show up to 90% contrast and are not quenched under off-axis magnetic field exceeding 100 mT, enabling <math xmlns="http://www.w3.org/1998/Math/MathML"><mi>μ</mi> <mspace></mspace> <mi>T</mi> <mo>/</mo> <msup><mrow><mi>Hz</mi></mrow> <mrow><mo>-</mo> <mn>1</mn> <mo>/</mo> <mn>2</mn></mrow> </msup> </math> sensitivity. Finally, we show how this system can be used to unambiguously determine the three components of a target magnetic field via the use of two bias fields. Alongside these features, the room-temperature operation and the nanometer-scale proximity enabled by the van der Waals host material further consolidate this system as a promising quantum sensing platform.