Enhanced sensitivity in microscale high-field NMR via nuclear-spin locking with N-V centers
Nitrogen-vacancy centers in diamond enable high-field NMR sensing at ambient conditions but struggle to track fast nuclear frequencies using standard microwave techniques. This work introduces a nuclear-spin locking approach that replaces free evolution with amplitude encoding, extending coherence times and boosting sensitivity by more than fourfold — a major step toward more precise high-field quantum NMR measurements.