High-Resolution Nanoscale AC Quantum Sensing in CMOS Compatible SiC

High-resolution nanoscale nuclear magnetic resonance (NMR) allows measurement of chemical structure at the single-molecule level for determining molecular dynamics. Until now, nitrogen vacancy centers in diamond have been the only platform to demonstrate single-defect NMR sensing at sub-Hz spectral resolution. Using a single silicon vacancy defect prepared under CMOS-compatible conditions in commercial 4H-silicon carbide at room temperature, we use the Synchronized Readout technique to measure a test signal. We achieve a spectral resolution of 0.33 Hz, necessary for understanding molecular structure, and estimate a magnetic sensitivity of 358 μT/$\sqrt{Hz}$ for our system. We also explore the necessary improvements for achieving single-proton spin sensitivity. Combining these results with future integrated photonics shows a promising path toward scalable nanoscale sensing for low-cost NMR spectrometers based on an industry-mature silicon carbide material.