Skip to main content
U.S. flag

An official website of the United States government

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Noncritical phasematching behavior in thin-film lithium niobate frequency converters



Paulina Kuo


We present a study of noncritical phasematching behavior in thin-film, periodically poled lithium niobate (PPLN) waveguides. Noncritical phasematching refers to designing waveguides so that the phasematching is insensitive to variations in waveguide thickness, width, or other parameters. For waveguide thickness (the dimension with greatest nonuniformity due to fabrication), we found that phasematching sensitivity can be minimized but not eliminated. We estimate limits on the acceptable thickness variation and discuss scaling with device length for second-harmonic generation and sum-frequency generation in thin-film PPLN frequency converters.
Optics Letters


Kuo, P. (2021), Noncritical phasematching behavior in thin-film lithium niobate frequency converters, Optics Letters, [online],, (Accessed April 23, 2024)
Created December 17, 2021, Updated November 29, 2022