Probing boron vacancy defects in hBN via single spin relaxometry
- Alex L. Melendez
- Ruotian Gong
- Guanghui He
- Yan Wang
- Yueh-Chun Wu
- Thomas Poirier
- Steven Randolph
- Sujoy Ghosh
- Liangbo Liang
- Stephen Jesse
- An-Ping Li
- Joshua T. Damron
- Benjamin J. Lawrie
- James H. Edgar
- Ivan V. Vlassiouk
- Chong Zu
- Huan Zhao
2026-03-10
Spin defects in solids offer promising platforms for quantum sensing and memory due to their long coherence times and optical addressability. Here, we integrate a single nitrogen-vacancy (NV) center in diamond with scanning probe microscopy to detect, read out, and spatially map spin-based quantum sensors at the nanoscale. Using the boron vacancy ( $${{{{\rm{V}}}}}_{{{{\rm{B}}}}}^{-}$$ V B − ) center in hexagonal boron nitride—an emerging two-dimensional spin system—as a model, we detect its electron spin resonance indirectly via changes in the spin relaxation time ( T 1 ) of a nearby NV center, eliminating the need for optical excitation or fluorescence detection of the $${{{{\rm{V}}}}}_{{{{\rm{B}}}}}^{-}$$ V B − . Cross-relaxation between NV and $${{{{\rm{V}}}}}_{{{{\rm{B}}}}}^{-}$$ V B − ensembles significantly reduces NV T 1 , enabling quantitative nanoscale mapping of defect densities beyond the optical diffraction limit and clear resolution of hyperfine splitting in isotopically enriched h 10 B 15 N. Our method demonstrates interactions between spin sensors in 3D and 2D materials, establishing NV centers as versatile probes for characterizing otherwise inaccessible spin defects.