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Updated: Apr 15, 2026
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Rejection of Fluorescence Background in Resonance and Spontaneous Raman Microspectroscopy
Published on: May 18, 2011
13.6K
Multiple quasi-phase-matching in nonlinear Raman-Nath diffraction
Optics Letters
|April 2, 2015
Summary
This study introduces a new method for designing 2D nonlinear photonic lattices to achieve efficient multiple quasi-phase-matched second harmonic generation. The approach significantly boosts the efficiency of generating multiple second harmonic beams via nonlinear Raman-Nath diffraction.
Area of Science:
- Nonlinear optics
- Photonics
- Materials science
Background:
- Efficient generation of multiple second harmonic beams is crucial for various photonic applications.
- Nonlinear Raman-Nath diffraction (NRND) is a key process for harmonic generation.
- Existing methods often suffer from low efficiency or lack precise control.
Purpose of the Study:
- To design a two-dimensional (2D) nonlinear photonic lattice for efficient multiple quasi-phase-matched second harmonic generation.
- To develop an analytical solution for calculating second harmonic intensity in 2D lattices.
- To enhance the efficiency of harmonic generation via NRND.
Main Methods:
- Employing the superposition of nonlinearity modulation to design the 2D nonlinear photonic lattice.
- Developing an analytical solution to calculate the second harmonic intensity.
- Investigating the nonlinear Raman-Nath diffraction (NRND) process.
Main Results:
- The proposed method enables efficient multiple quasi-phase-matched second harmonic generation.
- An analytical solution was successfully developed for rectangular 2D lattices.
- The designed lattice demonstrated a few orders of magnitude higher efficiency compared to nonphase-matched generation.
Conclusions:
- The superposition of nonlinearity modulation is an effective strategy for designing 2D nonlinear photonic lattices.
- The analytical solution provides a valuable tool for predicting and optimizing harmonic generation.
- This work offers a pathway to significantly improve the efficiency of multiple second harmonic beam generation.
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