Proximity-Induced Exchange Interaction: a New Pathway for Quantum Sensing using Spin Centers in Hexagonal Boron Nitride

Defects in hexagonal boron nitride (hBN), a two-dimensional van der Waals material, have raised wide range interest for its potential in various quantum applications. Due to hBN's 2D nature, spin center in hBN can be engineered in close proximity to target material, providing advantages over their 3D counterparts, such as nitrogen-vacancy (NV) center in diamond. Here we propose a novel quantum sensing protocol driven by exchange interaction between spin center in hBN and the underlying magnetic substrate induced by magnetic proximity effect. By first-principle calculation, we demonstrate the induced exchange interaction dominates over dipole-dipole interaction by orders of magnitude when in proximity. The interaction remains antiferromagnetic across all stacking configuration between the spin center in hBN and the target van der Waals magnets. Additionally, we explored the scaling behavior of the exchange field as a function of the spatial separation between the spin center and the targets.