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Updated: Aug 13, 2026
09:33
Demonstration of Equal-Intensity Beam Generation by Dielectric Metasurfaces
Published on: June 7, 2019
Intrinsic Chirality of Dielectric Metasurfaces Unlocked by Resonant Chiral Modes
Brijesh Kumar1,2, Pavel Tonkaev1, Ivan Toftul1
1Nonlinear Physics Center, Research School of Physics, Australian National University, Canberra, Australian Capital Territory2601, Australia.
Nano Letters
|August 12, 2026
Summary
Researchers demonstrated a new way to create optical chirality in nanophotonic structures. By using bilayer metasurfaces, they achieved strong circular dichroism, a key property for advanced optical devices.
Area of Science:
- Nanophotonics
- Dielectric Metasurfaces
- Chiroptical Response
Background:
- Controlling optical chirality at the subwavelength scale is crucial for nanophotonic applications.
- Achieving strong chiroptical responses in planar dielectric metasurfaces without chiral meta-atoms is difficult.
Purpose of the Study:
- To experimentally confirm a novel mechanism of metasurface chirality.
- To demonstrate resonantly enhanced circular dichroism in bilayer metasurfaces.
Main Methods:
- Fabrication of a free-standing silicon membrane metasurface.
- Breaking out-of-plane symmetry with a PMMA layer to activate chirality.
- Experimental confirmation of predicted chiral response.
Main Results:
- Demonstrated resonantly enhanced circular dichroism in the near-infrared spectrum.
- Observed chiral response governed by chiral photonic modes, interlayer coupling, and symmetry breaking.
- Confirmed theoretical predictions of mode-induced chirality.
Conclusions:
- Bilayer metasurfaces provide a simple and versatile platform for engineering chirality.
- This approach enables the development of compact planar photonic metadevices with strong chiral properties.
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