Nanoscale Vector Electric Field Imaging Using a Single Electron Spin

The ability to perform nanoscale electric field imaging of elementary charges at ambient temperatures will have diverse interdisciplinary applications. While the nitrogen-vacancy (NV) center in diamond is capable of high-sensitivity electrometry, demonstrations have so far been limited to macroscopic field features or detection of single charges internal to the diamond itself. In this work, we greatly extend these capabilities by using a shallow NV center to image the electric field of a charged atomic force microscope tip with nanoscale resolution. This is achieved by measuring Stark shifts in the NV spin-resonance due to AC electric fields. We demonstrate a near single-charge sensitivity of η = 5.3 charges/√Hz and subelementary charge detection (0.68e). This proof-of-concept experiment provides the motivation for further sensing and imaging of electric fields using NV centers in diamond.