Thinfilm lithiumniobateoninsulator (LNOI) has emerged as a superior integratedphotonics platform for linear, nonlinear, and electrooptics. Here we combine quasiphasematching, dispersion engineering, and tight mode confinement to realize nonlinear parametric processes with both high efficiency and wide wavelength tunability. On a millimeterlong, Zcut LNOI waveguide, we demonstrate efficient (
Periodically poled thinfilm lithium niobate (TFLN) waveguides have emerged as a leading platform for highly efficient frequency conversion in the nearinfrared. However, the commonly used silica bottomcladding results in high absorption loss at wavelengths beyond 2.5 µm. In this work, we demonstrate efficient frequency conversion in a TFLNonsapphire platform, which features high transparency up to 4.5 µm. In particular, we report generating midinfrared light up to 3.66 µm via differencefrequency generation of a fixed 1 µm source and a tunable telecom source, with normalized efficiencies up to
 NSFPAR ID:
 10250331
 Publisher / Repository:
 Optical Society of America
 Date Published:
 Journal Name:
 Optica
 Volume:
 8
 Issue:
 6
 ISSN:
 23342536
 Page Range / eLocation ID:
 Article No. 921
 Format(s):
 Medium: X
 Sponsoring Org:
 National Science Foundation
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