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Title: Spectrally separable photon-pair generation in dispersion engineered thin-film lithium niobate

Existing nonlinear-optic implementations of pure, unfiltered heralded single-photon sources do not offer the scalability required for densely integrated quantum networks. Additionally, lithium niobate has hitherto been unsuitable for such use due to its material dispersion. We engineer the dispersion and the quasi-phasematching conditions of a waveguide in the rapidly emerging thin-film lithium niobate platform to generate spectrally separable photon pairs in the telecommunications band. Such photon pairs can be used as spectrally pure heralded single-photon sources in quantum networks. We estimate a heralded-state spectral purity of >94% based on joint spectral intensity measurements. Further, a joint spectral phase-sensitive measurement of the unheralded time-integrated second-order correlation function yields a heralded-state purity of(86±<#comment/>5)%<#comment/>.

 
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Award ID(s):
2137723 1941583 1839197 1918549
NSF-PAR ID:
10368696
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Optics Letters
Volume:
47
Issue:
11
ISSN:
0146-9592; OPLEDP
Page Range / eLocation ID:
Article No. 2830
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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