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Title: Efficient and highly tunable second-harmonic generation in Z-cut periodically poled lithium niobate nanowaveguides

Thin-film lithium-niobate-on-insulator (LNOI) has emerged as a superior integrated-photonics platform for linear, nonlinear, and electro-optics. Here we combine quasi-phase-matching, dispersion engineering, and tight mode confinement to realize nonlinear parametric processes with both high efficiency and wide wavelength tunability. On a millimeter-long, Z-cut LNOI waveguide, we demonstrate efficient (1900±<#comment/>500%<#comment/>W−<#comment/>1cm−<#comment/>2) and highly tunable (−<#comment/>1.71nm/K) second-harmonic generation from 1530 to 1583 nm by type-0 quasi-phase-matching. Our technique is applicable to optical harmonic generation, quantum light sources, frequency conversion, and many other photonic information processes across visible to mid-IR spectral bands.

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Optics Letters
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Article No. 3789
0146-9592; OPLEDP
Optical Society of America
Sponsoring Org:
National Science Foundation
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