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Updated: Feb 9, 2026

Author Spotlight: Unveiling the Potential of VSFG Microscopy in Studying Mesoscopically Heterogeneous Self-Assembled Structures
Published on: December 1, 2023
Simultaneous sum-frequency and second-harmonic generation in a planar waveguide
Abstract:
In this paper, we analyze second-harmonic (SH) generation and sum-frequency (SF) generation in a planar waveguide configuration using 2D quasi-phase-matching (QPM) gratings and show possibility of simultaneous generation of sum frequency and second harmonic. It is shown that it is possible for the two generated frequencies to be noncollinear with respect to the incident pump waves with the SF and SH frequencies exiting at different angles along the planar waveguide, leading to ease of collection. Numerical simulations are performed in a potassium titanyl phosphate planar waveguide, and it is shown that the proposed planar waveguide configuration provides wavelength tunability and has greater conversion efficiencies than bulk configuration and larger bandwidth than channel waveguide configuration.
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