Chiral flatband in refractive index modulated metasurfaces

Area of Science:

• Photonics and Nanotechnology
• Chiroptical Metasurfaces
• Flatband Physics

Background:

• Flatband materials exhibit unique optical properties like slow light and high density of states.
• Chiroptical responses are crucial for various light-based technologies.
• Integrating flatband properties into metasurfaces can enhance chiroptical performance.

Purpose of the Study:

• To establish a theoretical framework for analyzing circular dichroism in metasurfaces with broken mirror symmetry.
• To design a metasurface exhibiting a pronounced flatband with enhanced chiroptical response.
• To explore the potential applications of such metasurfaces.

Main Methods:

• Theoretical framework development for analyzing circular dichroism.
• Modeling based on refractive index modulation and partial etching.
• Analysis of chiroptical responses across a range of incident angles.

Main Results:

• A theoretical framework for analyzing circular dichroism in broken mirror symmetry systems was established.
• A metasurface with a pronounced flatband and significant chiroptical response was designed.
• The designed metasurface demonstrated enhanced chiroptical performance at wide incidence angles.

Conclusions:

• The study presents a novel theoretical approach for designing flatband chiral metasurfaces.
• The developed metasurface shows promise for applications in chiral light sources, detectors, sensing, and enantioseparation.
• The findings are particularly relevant for applications requiring wide-angle chiroptical responses.