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Nearfield Vortex Dynamics of Supercell Bloch Modes.
Xiaona Ye1, Guangfeng Wang1, Xiaoyang Duan2
1Shanghai Jiao Tong University, State Key Laboratory of Photonics and Communications, School of Physics and Astronomy, Shanghai 200240, China.
Physical Review Letters
|July 31, 2025
Summary
We demonstrate a new method to control optical vortices in photonic crystals using paired rotations. This allows for tailored light-matter interactions and enhanced nonlinear optical effects like second harmonic generation.
Area of Science:
- Photonics
- Optical Physics
- Condensed Matter Physics
Background:
- Optical vortices are key in photonic crystals but limited by symmetry.
- Controlling nearfield vortex configurations is crucial for light-matter interactions.
Purpose of the Study:
- To demonstrate dynamic control of nearfield vortices in supercell photonic crystals.
- To explore how tailored vortex configurations impact light-matter interactions and nonlinear optics.
Main Methods:
- Introducing paired rotations of triangular structures in a supercell photonic crystal.
- Analyzing Bloch mode transitions and their associated vortex dynamics.
- Investigating nonlinear overlap and second harmonic generation.
Main Results:
- Achieved high-quality-factor Bloch mode transitions including evanescent valley modes, quasibound states in the continuum, frustrated modes, and quasivalleys.
- Observed distinct nearfield vortex distributions and nonlinear properties at each stage.
- Demonstrated enhanced second harmonic generation in frustrated modes due to asymmetric vortex configuration and optimized nonlinear overlap.
Conclusions:
- Paired-rotation strategy offers versatile design for supercell photonic crystals with unique vortex properties.
- The demonstrated control enables tailoring of light-matter interactions.
- Promising applications in lasing, nonlinear optics, and optical forces are presented.
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