We report room-temperature observations of CuZn-VS quantum emitters in individual ZnS:Cu nanocrystals (NCs). Using time-gated imaging, we isolate the distinct, ∼3-μs-long, red photoluminescence (PL) emission of CuZn-VS defects, enabling their precise identification and statistical characterization. The emitters exhibit distinct blinking and photon antibunching, consistent with individual NCs containing two to four CuZn-VS defects. The quantum emitters' PL spectra show a pronounced blue shift compared to NC dispersions, likely due to photochemical and charging effects. Emission polarization measurements of quantum emitters are consistent with a σ-character optical dipole transition and the symmetry of the CuZn-VS defect. These observations motivate further investigation of CuZn-VS defects in ZnS NCs for use in quantum technologies.
@article{arxiv.2501.11812,
title = {Room-temperature quantum emission from $\mathrm{Cu_{Zn}}$-$\mathrm{V_{S}}$ defects in ZnS:Cu colloidal nanocrystals},
author = {Yossef E. Panfil and Sarah M. Thompson and Gary Chen and Jonah Ng and Cherie R. Kagan and Lee C. Bassett},
journal= {arXiv preprint arXiv:2501.11812},
year = {2025}
}