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Updated: Jun 9, 2025
09:23
Quantum State Engineering of Light with Continuous-wave Optical Parametric Oscillators
Published on: May 30, 2014
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Optical moiré bound states in the continuum.
Haoyu Qin1,2, Shaohu Chen3, Weixuan Zhang4,5
1Key Laboratory of Advanced Optoelectronic Quantum Architecture and Measurements of Ministry of Education, School of Physics, Beijing Institute of Technology, 100081, Beijing, China.
Nature Communications
|October 21, 2024
Summary
Researchers created moiré photonic crystals exhibiting bound states in the continuum (BICs). These structures achieve high Q-factors and flat bands, overcoming limitations in optical devices for better performance and disorder resilience.
Area of Science:
- Optics and Photonics
- Condensed Matter Physics
- Materials Science
Background:
- Trapping electromagnetic waves is crucial for optical science and technology.
- Photonic bound states in the continuum (BICs) offer a method for wave trapping with applications in lasers and sensors.
- Existing BICs struggle with simultaneous high Q-factors, flat bands, and wide-angle responses, limiting practical use.
Purpose of the Study:
- To theoretically demonstrate the construction of moiré BICs in one-dimensional photonic crystal (PhC) slabs.
- To achieve high Q-factors across the entire moiré flat band.
- To overcome limitations of previous BIC designs regarding performance and disorder.
Main Methods:
- Theoretical demonstration of moiré BIC construction in 1D PhC slabs.
- Numerical validation of eliminating radiation loss by aligning topological polarization charges with diffraction channels.
- Experimental fabrication and characterization of the designed 1D moiré PhC slab.
Main Results:
- Achieved high-Q resonances across the entire moiré flat band by suppressing far-field radiation.
- Demonstrated a slow decay of Q-factors in momentum space away from moiré BICs.
- Observed high Q-factors in the moiré flat band that remain robust against structural disorder.
Conclusions:
- Successfully constructed moiré BICs in 1D PhC slabs with high Q-factors and flat-band properties.
- The design enables efficient optical devices with wide-angle responses, overcoming previous limitations.
- Introduced a novel approach for exploring BICs within moiré superlattices.
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