Sensing and atomic-scale structure analysis of single nuclear-spin clusters in diamond

Being able to sense nuclear spin dimers is an important next step towards single-molecule structural analysis from NMR measurements. Now the sensing of a single 13 C– 13 C nuclear spin dimer near a nitrogen–vacancy centre in diamond is reported, together with a structural characterization at atomic-scale resolution. Single-molecule nuclear magnetic resonance is a current challenge in the field of magnetic resonance spectroscopy and has important applications in chemical analysis and quantum computing. Through decoherence measurements of nitrogen–vacancy centres under dynamical decoupling control, the sensing of a single 13 C nuclear spin at nanometre distance has recently been realized 1 , 2 , 3 . A further step towards the ultimate goal of structure analysis of single molecules would be the direct measurement of the interactions within single nuclear-spin clusters 4 . Here we sense a single 13 C– 13 C nuclear-spin dimer located about 1 nm from the nitrogen–vacancy centre and characterize the interaction (∼690 Hz) between the two nuclear spins. From the measured interaction we derive the spatial configuration of the dimer with atomic-scale resolution. These results indicate that, in combination with advanced material-surface engineering, central spin decoherence under dynamical decoupling control may be a useful probe for nuclear magnetic resonance single-molecule structure analysis.