Frequency-Tracking ESR Achieves Minute-Scale 3D Magnetic Mapping at 54 μT/√Hz with hBN Boron-Vacancy Sensors
This preprint demonstrates that ESR frequency tracking converts slow point-by-point ODMR mapping into a fast, real-time technique suitable for dynamic nanoscale magnetometry. The 10-fold reduction in acquisition time and ambient-condition operation open pathways for integration into scanning-probe platforms used in electronics failure analysis and biological magnetic imaging. Remaining challenges include contrast optimization and extension to vectorial sensing without mechanical rotation.
The arXiv preprint describes a frequency-tracking protocol that continuously monitors the ODMR spectrum of localized VB- centers rather than acquiring full spectra at each pixel. By locking to the resonance frequency in real time, the method reduced integration time per point enough to complete a full 3D scan of a conical tip field in a few minutes while measuring gradients of 3.6 ± 0.2 μT/nm and tracking fields up to 6 mT/s. Sample positioning was controlled to reconstruct the vector field component along the sensor axis with sub-micron lateral resolution set by the optical diffraction limit.
Pessoa et al.: Within 24 months, frequency-tracked VB- hBN sensors will demonstrate <20 μT/√Hz sensitivity in a commercial scanning-probe instrument under ambient conditions.
Sources (2)
- [1]Primary Source(https://arxiv.org/abs/2608.20502)
- [2]Supporting Source(https://arxiv.org/pdf/2608.20502.pdf)