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Using Microwave and Macroscopic Samples of Dielectric Solids to Study the Photonic Properties of Disordered Photonic Bandgap Materials
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Theory for Twisted Bilayer Photonic Crystal Slabs
Beicheng Lou1, Nathan Zhao1, Momchil Minkov2
1Department of Applied Physics, and Ginzton Laboratory, Stanford University, Stanford, California 94305, USA.
Physical Review Letters
|April 16, 2021
Summary
We analyze twisted bilayer photonic crystals, revealing tunable optical properties and chiral behavior. This research offers a theoretical basis for understanding complex photonic systems.
Area of Science:
- Photonics and optical physics.
- Condensed matter physics.
Background:
- Photonic crystal slabs are crucial for controlling light.
- Twisted bilayer structures introduce unique physical phenomena.
- Existing methods often face limitations with arbitrary twist angles.
Purpose of the Study:
- To analyze the scattering properties of twisted bilayer photonic crystal slabs.
- To develop a method applicable to arbitrary twist angles.
- To understand the tunable optical and chiral behaviors in these systems.
Main Methods:
- Utilizing a high-dimensional plane wave expansion method.
- Overcoming limitations of the supercell approximation.
- Employing a correspondence relation for semianalytical accounting.
Main Results:
- Demonstrated strongly tunable resonance properties.
- Observed strongly tunable resonant chiral behavior.
- The method is applicable for arbitrary twist angles.
Conclusions:
- The study provides a robust theoretical foundation for twisted multilayer photonic crystals.
- Enables prediction and understanding of rich optical physics.
- Highlights the potential for novel photonic device applications.
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