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Title: Mid-infrared nonlinear optics in thin-film lithium niobate on sapphire

Periodically poled thin-film lithium niobate (TFLN) waveguides have emerged as a leading platform for highly efficient frequency conversion in the near-infrared. However, the commonly used silica bottom-cladding results in high absorption loss at wavelengths beyond 2.5 µm. In this work, we demonstrate efficient frequency conversion in a TFLN-on-sapphire platform, which features high transparency up to 4.5 µm. In particular, we report generating mid-infrared light up to 3.66 µm via difference-frequency generation of a fixed 1 µm source and a tunable telecom source, with normalized efficiencies up to200%<#comment/>/Wcm2. These results show TFLN-on-sapphire to be a promising platform for integrated nonlinear nanophotonics in the mid-infrared.

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Award ID(s):
1918549 2011363
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ;
Publisher / Repository:
Optical Society of America
Date Published:
Journal Name:
Page Range / eLocation ID:
Article No. 921
Medium: X
Sponsoring Org:
National Science Foundation
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