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Updated: May 15, 2025
11:08
Fabrication And Characterization Of Photonic Crystal Slow Light Waveguides And Cavities
Published on: November 30, 2012
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Chiral lasing enabled by strong coupling.
Huachun Deng1, Xiong Jiang1, Yao Zhang1
1Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System, Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic Systems, Harbin Institute of Technology, Shenzhen 518055, P. R. China.
Science Advances
|April 9, 2025
Summary
Researchers engineered chiral metasurfaces to achieve high-purity chiral laser emission by coupling two resonances. This breakthrough enables directional chiral lasing, overcoming limitations of conventional quasi-bound states in the continuum (quasi-BIC) lasers.
Area of Science:
- Photonics
- Metamaterials
- Quantum Optics
Background:
- Chiral quasi-bound states in the continuum (quasi-BICs) are high-Q resonances in photonic structures.
- These states support chiral lasing but are typically limited to vertical emission.
- Engineering in-plane and out-of-plane asymmetries breaks symmetry-protected optical states.
Purpose of the Study:
- To explore the coupling between two resonances in a chiral metasurface.
- To introduce a novel mechanism for high-purity chiral laser emission.
- To enable directional chiral lasing beyond conventional vertical emission.
Main Methods:
- Engineered a chiral metasurface to induce strong coupling between two resonances with orthogonal polarizations.
- Utilized the inherent phase difference of resonances for coherent destruction of the decay channel.
- Experimentally verified the mechanism through transmission spectra, angle-resolved photoluminescence, and laser emission measurements.
Main Results:
- Achieved strong coupling between two nearly orthogonal polarized resonances in the engineered chiral metasurface.
- Demonstrated that the phase difference maximizes chirality in one of the hybrid modes, leading to high-Q factor.
- Successfully realized high-purity chiral laser emission.
Conclusions:
- The proposed mechanism allows for breaking restrictions on conventional chiral quasi-BIC lasing.
- This approach enables the realization of chiral emission at any designed direction.
- The findings pave the way for versatile chiral photonic devices.
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