Fig. 5. Nuclear magnetic resonance (NMR) with nitrogen–vacancy (NV) centres.

a, Single-NV and NV-ensemble NMR set-ups. b,c, Pulse sequences used for NMR detection with NV centres: XY8-k (XY8 is a sequence of microwave pulses with X and Y phase shifts and is repeated k times, part b) and coherently averaged synchronized readout (CASR, part c). d, NMR spectrum detected by NV ensembles showing resolved chemical shift. e, Inset: image of a grating etched on a fluorine-enriched microsphere on an atomic force microscope tip. Main image: line scan of the NMR spectrum detected by a single NV centre as the sphere is moved over the NV centre. Parts a,b adapted with permission from ref. ¹⁰⁰, Springer Nature Ltd. Parts c,d adapted with permission from ref. ⁶,  Springer Nature Ltd. Part e adapted with permission from ref. ¹¹⁵,  Springer Nature Ltd.