Wide Field Imaging of Low-dimensional Magnetism by 2D Spin Defects

Quantum sensing using atomic spin defects serves as a transformative method to explore the local magnetic properties of solid-state systems with optimal spatial and field sensitivity. The flourishing catalog of van der Waals two-dimensional (2D) materials has provided a diverse new playground to enrich this field. In comparison with their conventional counterparts imbedded in three-dimensional solid-state-media, spin defects hosted by 2D materials exhibit improved versatility and remarkable compatibility to device integration. In this work, we report nanoscale quantum sensing and imaging of exfoliated 2D ferromagnet Fe₃GeTe₂ flakes by boron vacancy spin defects in an adjacent hexagonal boron nitride capping layer. Exploiting the wide field magnetometry method, we directly imaged the local magnetic texture of the Fe₃GeTe₂ flake and its characteristic temperature and field dependent magnetization evolution behavior. We highlight that the presented quantum sensing platform can be extended naturally to a large family of miniaturized 2D van der Waals heterostructures, bringing ample opportunities to the forefront research of quantum material and quantum sensing.