Magnetic field imaging with nitrogen-vacancy ensembles

Abstract

We demonstrate a method of imaging spatially varying magnetic fields using a\nthin layer of nitrogen-vacancy (NV) centers at the surface of a diamond chip.\nFluorescence emitted by the two-dimensional NV ensemble is detected by a CCD\narray, from which a vector magnetic field pattern is reconstructed. As a\ndemonstration, AC current is passed through wires placed on the diamond chip\nsurface, and the resulting AC magnetic field patterns are imaged using an\necho-based technique with sub-micron resolution over a 140 \\mu m x 140 \\mu m\nfield of view, giving single-pixel sensitivity ~100 nT/\\sqrt{Hz}. We discuss\nongoing efforts to further improve sensitivity and potential bioimaging\napplications such as real-time imaging of activity in functional, cultured\nnetworks of neurons.\n