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Updated: Jun 3, 2026
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The Generation of Higher-order Laguerre-Gauss Optical Beams for High-precision Interferometry
Published on: August 12, 2013
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Efficient generation of octave-separating orbital angular momentum beams via forked grating array in lithium niobite
Xinyu Liu1, Dan Wei2, Chun Chang1
1State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics, Sun Yat-Sen University, Guangzhou 510275, China.
Nanophotonics (Berlin, Germany)
|December 5, 2024
Summary
Researchers generated multiple orbital angular momentum (OAM) beams at fundamental and second harmonic wavelengths using a novel lithium niobate platform. This advance enhances optical communication and data storage capabilities.
Area of Science:
- Nonlinear Optics
- Photonic Crystals
- Structured Light
Background:
- Orbital angular momentum (OAM) of light is crucial for fundamental physics and applications like optical communication.
- Combined schemes for OAM generation offer potential for increased communication channels but struggle with conversion efficiency.
- Lithium niobate nonlinear photonic crystals provide a versatile platform for manipulating light properties.
Purpose of the Study:
- To demonstrate the generation of multiple OAM beams at both fundamental and second harmonic (SH) wavelengths.
- To enhance OAM beam generation using linear and nonlinear Bragg diffraction (quasi-phase matching).
- To explore the potential for parallel detection of OAM states in optical communications.
Main Methods:
- Utilized a three-dimensional forked grating array with spatial χ(1) and χ(2) distributions in a lithium niobate nonlinear photonic crystal.
- Employed linear Bragg diffraction for fundamental OAM beam enhancement.
- Employed nonlinear Bragg diffraction (quasi-phase matching) for SH OAM beam enhancement.
Main Results:
- Successfully generated multiple OAM beams at fundamental and SH wavelengths.
- Achieved high conversion efficiency of 60.45% for linear OAM beams.
- Demonstrated nonlinear OAM beam generation with efficiencies of 1.08 × 10-4 W-1.
Conclusions:
- The developed method enables wavelength or angle tuning for enhancing OAM beams with variable topological charges.
- This work presents a promising approach for parallel detection of OAM states, advancing optical communication.
- The findings extend beyond OAM to the broader control of structured light via cascaded linear and nonlinear processes.
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