Imaging the local charge environment of nitrogen-vacancy centers in diamondThomas Mittiga, Satcher Hsieh, Chong Zu, Bryce Kobrin, Francisco Machado, Prabudhya Bhattacharyya, Nicholas Rui, Andrey Jarmola, Soonwon Choi, Dmitry Budker, Norman Y. Yao
Characterizing the local internal environment surrounding solid-state spin defects is crucial to harnessing them as nanoscale sensors of external fields. This is especially germane to the case of defect ensembles which can exhibit a complex interplay between interactions, internal fields and lattice strain. Working with the nitrogen-vacancy (NV) center in diamond, we demonstrate that local electric fields dominate the magnetic resonance behavior of NV ensembles at low magnetic field. We introduce a simple microscopic model that quantitatively captures the observed spectra for samples with NV concentrations spanning over two orders of magnitude. Motivated by this understanding, we propose and implement a novel method for the nanoscale localization of individual charges within the diamond lattice; our approach relies upon the fact that the charge induces an NV dark state which depends on the electric field orientation.