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arXiv · 2207.10477

Magnetic imaging with spin defects in hexagonal boron nitride

P. Kumar·F. Fabre·A. Durand·T. Clua-Provost·J. Li·J. H. Edgar·N. Rougemaille·J. Coraux·X. Marie·P. Renucci·C. Robert·I. Robert-Philip·B. Gil·G. Cassabois·A. Finco·V. Jacques
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Abstract

Optically-active spin defects hosted in hexagonal boron nitride (hBN) are promising candidates for the development of a two-dimensional (2D) quantum sensing unit. Here, we demonstrate quantitative magnetic imaging with hBN flakes doped with negatively-charged boron-vacancy (V$_{\rm B}^-$) centers through neutron irradiation. As a proof-of-concept, we image the magnetic field produced by CrTe$_2$, a van der Waals ferromagnet with a Curie temperature slightly above $300$ K. Compared to other quantum sensors embedded in 3D materials, the advantages of the hBN-based magnetic sensor described in this work are its ease of use, high flexibility and, more importantly, its ability to be placed in close proximity to a target sample. Such a sensing unit will likely find numerous applications in 2D materials research by offering a simple way to probe the physics of van der Waals heterostructures.

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P. Kumar, F. Fabre, A. Durand, T. Clua-Provost, J. Li, J. H. Edgar, N. Rougemaille, J. Coraux, X. Marie, P. Renucci, C. Robert, I. Robert-Philip, B. Gil, G. Cassabois, A. Finco, V. Jacques. 2022-07-21. Magnetic imaging with spin defects in hexagonal boron nitride. https://doi.org/10.1103/physrevapplied.18.l061002

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