Pham, LinhLe Sage, DavidStanwix, Paul L.Yeung, Tsun KwanGlenn, DavidTrifonov, AlexeiCappellaro, PaolaHemmer, PhilipLukin, MikhailPark, HongkunYacoby, AmirWalsworth, Ronald2012-11-272011Pham, Linh M., David Le Sage, Paul L. Stanwix, Tsun K. Yeung, David R. Glenn, Alexei Trifonov, Paola Cappellaro, et al. 2011. Magnetic field imaging with nitrogen-vacancy ensembles. New Journal of Physics 13(4): 045021.1367-2630http://nrs.harvard.edu/urn-3:HUL.InstRepos:9949242We demonstrate a method of imaging spatially varying magnetic fields using a thin layer of nitrogen-vacancy (NV) centers at the surface of a diamond chip. Fluorescence emitted by the two-dimensional NV ensemble is detected by a CCD array, from which a vector magnetic field pattern is reconstructed. As a demonstration, ac current is passed through wires placed on the diamond chip surface, and the resulting ac magnetic field patterns are imaged using an echo-based technique with sub-micron resolution over a \(140 \mu m\) x \(140 \mu m\) field of view, giving single-pixel sensitivity \(\sim 100 nT / \sqrt{Hz}\). We discuss ongoing efforts to further improve the sensitivity, as well as potential bioimaging applications such as real-time imaging of activity in functional, cultured networks of neurons.en-USdiamondspinimplantationcentersJournal Article2012-11-2710.1088/1367-2630/13/4/045021