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arXiv · 2501.11812

Room-temperature quantum emission from $\mathrm{Cu_{Zn}}$-$\mathrm{V_{S}}$ defects in ZnS:Cu colloidal nanocrystals

Yossef E. Panfil·Sarah M. Thompson·Gary Chen·Jonah Ng·Cherie R. Kagan·Lee C. Bassett
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Abstract

We report room-temperature observations of $\mathrm{Cu_{Zn}}$-$\mathrm{V_{S}}$ quantum emitters in individual ZnS:Cu nanocrystals (NCs). Using time-gated imaging, we isolate the distinct, $\sim$3-$\mu$s-long, red photoluminescence (PL) emission of $\mathrm{Cu_{Zn}}$-$\mathrm{V_{S}}$ defects, enabling their precise identification and statistical characterization. The emitters exhibit distinct blinking and photon antibunching, consistent with individual NCs containing two to four $\mathrm{Cu_{Zn}}$-$\mathrm{V_{S}}$ 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 $\sigma$-character optical dipole transition and the symmetry of the $\mathrm{Cu_{Zn}}$-$\mathrm{V_{S}}$ defect. These observations motivate further investigation of $\mathrm{Cu_{Zn}}$-$\mathrm{V_{S}}$ defects in ZnS NCs for use in quantum technologies.

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Yossef E. Panfil, Sarah M. Thompson, Gary Chen, Jonah Ng, Cherie R. Kagan, Lee C. Bassett. 2025-01-21. Room-temperature quantum emission from $\mathrm{Cu_{Zn}}$-$\mathrm{V_{S}}$ defects in ZnS:Cu colloidal nanocrystals. https://arxiv.org/abs/2501.11812

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