Probing Remote Nuclear Magnetic Moments in hBN with VB Electron Spin

Abstract: Since the initial discovery of optically addressable spins of the negatively charged boron vacancy defect (VB) in hexagonal boron nitride (hBN), substantial progress has been made, enabling promising applications in quantum sensing, information processing, and simulations. A deep understanding of the VB (electron): hBN (nuclear) spin systems is crucial for realizing these potentials. In this article, we employ Electron Nuclear Double Resonance (ENDOR) to demonstrate the sensing of dis tant nuclear spins via the VB electron spin. We identify the nature and localization of the probed nuclear magnetic moments as 14N spins localized 0.4 nm away from the vacancy and resolve the energies of the corresponding interactions. Density Functional Theory (DFT) calculations further confirm these findings, providing a detailed description of the interactions between the VB electron spin and surrounding nitrogen atoms in different shells. The results establish the VB electron spin as a promising tool for developing novel van der Waals material-based nuclear magnetic resonance (NMR) probes, advancing the understanding of spin physics in hBN, and unlocking its potential to study distant nuclear spin interactions in the host.