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Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces
Published on: June 7, 2019
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Chiral Bilayer All-Dielectric Metasurfaces.
Katsuya Tanaka1,2, Dennis Arslan1, Stefan Fasold1
1Institute of Applied Physics, Abbe Center of Photonics, Friedrich Schiller University Jena, Albert-Einstein-Straße 15, 07745 Jena, Germany.
ACS Nano
|November 12, 2020
Summary
Researchers developed novel 3D chiral dielectric metasurfaces for high-efficiency ultrathin circular polarizers. These structures achieve record circular dichroism and optical activity by utilizing multipolar resonances with minimal losses.
Area of Science:
- Photonics and Nanotechnology
- Chiroptical Metasurfaces
- Plasmonics and Nanophotonics
Background:
- Three-dimensional chiral plasmonic metasurfaces show promise for circular polarizers and chiral sensing.
- High absorption losses in metallic systems hinder the efficiency of plasmonic devices.
- Need for high-efficiency, low-loss chiral nanostructures for advanced optical applications.
Purpose of the Study:
- To experimentally and numerically demonstrate three-dimensional chiral dielectric metasurfaces.
- To examine the chiro-optical properties of these dielectric metasurfaces.
- To achieve record high circular dichroism and optical activity using dielectric nanostructures.
Main Methods:
- Fabrication and characterization of 3D chiral dielectric metasurfaces.
- Numerical simulations to understand the underlying optical resonances.
- Investigation of electric and magnetic dipolar resonance excitation within chiral structures.
Main Results:
- Demonstration of 3D chiral dielectric metasurfaces with multipolar resonances.
- Achieved record high circular dichroism (0.7) and optical activity (2.67 × 105 degree/mm).
- Attributed high performance to low dissipative loss in dielectric materials and chiral supermode formation.
Conclusions:
- Highlighting mechanisms for maximizing chiral response in photonic nanostructures.
- Dielectric metasurfaces offer a pathway to high-efficiency, ultrathin polarizing elements.
- Potential for integration into miniaturized devices and integrated circuits.
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