Imaging dark charge emitters in diamond via carrier-to-photon conversion

TL;DR

This paper introduces a novel imaging technique that detects dark charge emitters in diamond by converting charge states into detectable photon signals, enhancing the visualization of otherwise invisible defects.

Contribution

The study presents a new charge-to-photon conversion method for imaging non-fluorescent point defects in diamond, expanding defect detection capabilities.

Findings

Enabled imaging of non-fluorescent charge emitters

Demonstrated position-dependent fluorescence changes

Potential applicability to other wide-bandgap materials

Abstract

The application of color centers in wide-bandgap semiconductors to nanoscale sensing and quantum information processing largely rests on our knowledge of the surrounding crystalline lattice, often obscured by the countless classes of point defects the material can host. Here we monitor the fluorescence from a negatively charged nitrogen-vacancy (NV-) center in diamond as we illuminate its vicinity. Cyclic charge state conversion of neighboring point defects sensitive to the excitation beam leads to a position-dependent stream of photo-generated carriers whose capture by the probe NV- leads to a fluorescence change. This "charge-to-photon" conversion scheme allows us to image other individual point defects surrounding the probe NV, including non-fluorescent "single-charge emitters" that would otherwise remain unnoticed. Given the ubiquity of color center photo-chromism, this strategy may likely find extensions to material systems other than diamond.