Colloidal 2D WS2 nanosheets exhibiting high-purity single photon emission
Abstract
The search for quantum emitters, delivering single photons "on demand" at cryogenic and elevated temperatures for photonic technologies is ever progressing. For example, micrometer-sized WS2 monolayers exhibit single photon emission by elaborated local defect or strain engineering. Here, we show that wet-chemically synthesised monolayered two-dimensional (2D) WS2 nano sheets (NSs) with lateral sizes of 14 (+/- 6 nm) readily emit single photons from exciton recombination without the need for substrate-induced patterning, strain/defect engineering or spectral filtering. Single particle spectroscopy of 70 individual NSs shows photoluminescence from excitons (2.02 eV), trios (1.94 eV) and defect-localized states (1.85 eV) with fast emission (t1<0.2 ns, t2=3.2 ns), allowing highly frequent excitation cycles. Pulsed at 80 MHz, colloidal WS2 NSs exhibit limited spectral diffusion, no blinking and distinct photon antibunching (g2(0)=0.07 at 5 K), thereby tackling challenges of established colloidal quantum dot systems (blinking, longer emission cycles), while retaining high single photon purity as key quality of deterministic quantum emitters.
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BibTeX
@misc{xemaire2026colloidal,
title = {{Colloidal 2D WS2 nanosheets exhibiting high-purity single photon emission}},
author = {Markus Xemaire and Jakob Keck and Marco Kögel and Marc Brecht and Jannik C. Meyer and Alfred J. Meixner and Jannika Lauth},
howpublished = {arXiv},
year = {2026},
month = nov,
doi = {10.48550/arxiv.2611.06144},
eprint = {2611.06144},
archivePrefix = {arXiv},
url = {https://arxiv.org/abs/2611.06144},
note = {CC BY-NC-ND 4.0},
}
RIS
TY - UNPB
TI - Colloidal 2D WS2 nanosheets exhibiting high-purity single photon emission
AU - Markus Xemaire
AU - Jakob Keck
AU - Marco Kögel
AU - Marc Brecht
AU - Jannik C. Meyer
AU - Alfred J. Meixner
AU - Jannika Lauth
PY - 2026
DA - 2026/11/04
PB - arXiv
DO - 10.48550/arxiv.2611.06144
UR - https://arxiv.org/abs/2611.06144
AB - The search for quantum emitters, delivering single photons "on demand" at cryogenic and elevated temperatures for photonic technologies is ever progressing. For example, micrometer-sized WS2 monolayers exhibit single photon emission by elaborated local defect or strain engineering. Here, we show that wet-chemically synthesised monolayered two-dimensional (2D) WS2 nano sheets (NSs) with lateral sizes of 14 (+/- 6 nm) readily emit single photons from exciton recombination without the need for substrate-induced patterning, strain/defect engineering or spectral filtering. Single particle spectroscopy of 70 individual NSs shows photoluminescence from excitons (2.02 eV), trios (1.94 eV) and defect-localized states (1.85 eV) with fast emission (t1<0.2 ns, t2=3.2 ns), allowing highly frequent excitation cycles. Pulsed at 80 MHz, colloidal WS2 NSs exhibit limited spectral diffusion, no blinking and distinct photon antibunching (g2(0)=0.07 at 5 K), thereby tackling challenges of established colloidal quantum dot systems (blinking, longer emission cycles), while retaining high single photon purity as key quality of deterministic quantum emitters.
ER -