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Published on: June 5, 2019
Metasurface-Enhanced Momentum-Resolved Circular Dichroism Spectroscopy
Remi Sydelle Dado1, Priyanuj Bordoloi2, Yanyu Xiong2
1Department of Chemistry, Stanford University, 33 Campus Drive, Stanford, California 94305, United States.
Nano Letters
|May 14, 2026
Summary
This study introduces a new method using achiral nanodisks to enhance and measure molecular circular dichroism (CD) signals. It effectively separates molecular CD from artifact signals for precise chirality detection.
Area of Science:
- Nanophotonics
- Chiroptics
- Spectroscopy
Background:
- Nanophotonic resonators can amplify weak molecular circular dichroism (CD) signals.
- Structural chirality can interfere with accurate CD measurements.
Purpose of the Study:
- To develop an artifact-free method for chiroptical enhancement and measurement.
- To enable sensitive detection of molecular chirality and enantiomeric purity.
Main Methods:
- Developed an achiral nanodisk array and angle-resolved spectral measurement approach.
- Utilized circular polarization-resolved momentum-space spectroscopy.
- Designed silicon nitride nanodisks for enhanced optical chirality.
Main Results:
- Successfully deconvoluted molecular and substrate signals, enabling artifact-free enhancement.
- Achieved a simulated ~150-fold enhancement in optical chirality density.
- Validated enhancement of low concentration and enantiomeric excess (ee) CD signals (down to 0.1 mM and 1-25% ee).
Conclusions:
- Momentum-resolved, metasurface-enhanced CD spectroscopy offers a reliable path for sensitive molecular chirality detection.
- The developed approach allows for accurate assessment of enantiomeric purity.
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