Sensing single remote nuclear spins

The detection of single nuclear spins would be useful for fields ranging from basic science to quantum information technology. However, although sensing based on diamond defects1,2 and other methods3 have shown high sensitivity1,2,3, they have not been capable of detecting single nuclear spins, and defect-based techniques further require strong defect–spin coupling4,5. Here, we present the detection and identification of single and remote 13C nuclear spins embedded in nuclear spin baths surrounding a single electron spin of a nitrogen-vacancy centre in diamond. We are able to amplify and detect the weak magnetic field noise (∼10 nT) from a single nuclear spin located ∼3 nm from the centre using dynamical decoupling control6,7,8,9,10, and achieve a detectable hyperfine coupling strength as weak as ∼300 Hz. We also confirm the quantum nature of the coupling, and measure the spin-defect distance and the vector components of the nuclear field. The technique marks a step towards imaging, detecting and controlling nuclear spins in single molecules.