Magnetic imaging with spin defects in hexagonal boron nitride

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 − B ) centers through neutron irradiation. As a proof-of-concept, we image the magnetic field produced by CrTe2, 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.

Quantum Emitters in Hexagonal Boron Nitride

“…This multitude of creation methods, a consequence of the simple monovacancy structure of the defect, allows for precise defect engineering and placement, for instance to couple V B – defects to photonic structures ,− and for sensing applications. Proof-of-principle demonstrations of quantum imaging have been reported, − using dense layers of V B – defects created by ion irradiation in thin hBN flakes, with the flake placed on top of a sample of interest. Example results are given in Figure e,f which show magnetic field and temperature images obtained by spatially mapping the ODMR spectrum of the hBN flake stacked onto a van der Waals magnetic flake.…”