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Title: Heralded Generation of Correlated Photon Pairs from CdS/CdSe/CdS Quantum Shells
Quantum information processing demands efficient quantum light sources (QLS) capable of producing high-fidelity single photons or entangled photon pairs. Single epitaxial quantum dots (QDs) have long been proven to be efficient sources of deterministic single photons; however, their production via molecular-beam epitaxy presents scalability challenges. Conversely, colloidal semiconductor QDs offer scalable solution processing and tunable photoluminescence but suffer from broader linewidths and unstable emissions. This leads to spectrally inseparable emission from exciton (X) and biexciton (XX) states, complicating the production of single photons and triggered photon pairs. Here, we demonstrate that colloidal semiconductor quantum shells (QSs) achieve significant spectral separation (~ 75-80 meV) and long temporal stability of X and XX emissive states, enabling the observation of exciton-biexciton bunching in colloidal QDs. Our low-temperature single-particle measurements show cascaded XX-X emission of single photon pairs for over 200 seconds, with minimal overlap between X and XX features. The X-XX distinguishability allows for an in-depth theoretical characterization of cross-correlation strength, placing it in perspective with photon pairs of epitaxial counterparts. These findings highlight a strong potential of semiconductor quantum shells for applications in quantum information processing.  more » « less
Award ID(s):
2347622 2208834
PAR ID:
10559227
Author(s) / Creator(s):
; ; ; ; ; ; ; ;
Publisher / Repository:
ACS Pubs
Date Published:
Journal Name:
ACS Nano
Volume:
18
Issue:
44
ISSN:
1936-0851
Page Range / eLocation ID:
30863 to 30870
Subject(s) / Keyword(s):
quantum information, entangled photon pair, quantum dot, semiconductor, exciton, biexciton, quantum shell
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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