Quantum electrometry of non-volatile space charges in diamond

The microscopic electric environment surrounding a spin defect in a wide-bandgap semiconductor plays a determining role in the spin coherence and charge stability of a given qubit and has an equally important role in defining the electrical properties of the host material. Here, we use electrometry of quantum defects embedded within a diamond to observe stable, micron-scale space charge distributions formed from trapped photogenerated charges. These space charges grow under optical illumination in the presence of an applied electric field, eventually screening the applied electric field entirely over a spatial extent of tens of microns due to charge carrier drift and capture. Our measurements suggest that these space charge fields originate from widely-dispersed spatial configurations of nitrogen charges. Our results have important consequences for electrometry and photoelectric detection using qubits in wide-bandgap semiconductors.