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Polarization-sensitive switchable display through critical coupling between graphene and a quasi-BIC
Zonglin Li1,2, Guozheng Nie1,2,3, Zhiquan Chen3
1School of Physics and Electronic Science, Hunan University of Science and Technology, Xiangtan, 411201, Hunan, China. gzhnie@hnust.edu.cn.
Physical Chemistry Chemical Physics : PCCP
|November 30, 2022
Summary
Researchers developed a dielectric metasurface to boost light-matter interactions in graphene. This metasurface enables tunable light absorption and polarization-controlled switching, paving the way for advanced nanophotonic devices.
Area of Science:
- Optics and Photonics
- Materials Science
Background:
- Enhanced light-matter interaction is crucial for nanophotonic devices.
- Optical bound states in the continuum (BICs) can achieve this enhancement.
Purpose of the Study:
- To propose a dielectric metasurface for enhanced light-matter interactions in graphene.
- To investigate the tunability and potential applications of this system.
Main Methods:
- Designed a dielectric metasurface exhibiting a symmetry-protected bound state in the continuum (BIC).
- Broken in-plane symmetry to transform the BIC into a quasi-BIC with a high quality factor.
- Introduced a graphene monolayer and optimized parameters for critical coupling.
Main Results:
- Observed enhanced absorption of graphene due to quasi-BIC resonance.
- Achieved a tunable absorber by optimizing graphene Fermi energy and metasurface asymmetry.
- Demonstrated efficient modulation of absorption intensity (up to 95.4%) by varying incident light polarization.
Conclusions:
- The proposed metasurface effectively enhances light-matter interactions in graphene.
- The system demonstrates potential for polarization-controlled tunable absorbers.
- Potential applications include polarization-switched digital switches and image displays without structural modifications.
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