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Electrophoretic Crystallization of Ultrathin High-performance Metal-organic Framework Membranes
Published on: August 16, 2018
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High-Performance Ultrathin Active Chiral Metamaterials.
Zilong Wu1, Xiaodong Chen2, Mingsong Wang1
1Department of Mechanical Engineering, Materials Science and Engineering Program, and Texas Materials Institute , The University of Texas at Austin , Austin , Texas 78712 , United States.
ACS Nano
|May 1, 2018
Summary
Ultrathin chiral metamaterials with tunable optical properties were developed for ultrasensitive impurity detection. These active chiral metamaterials exhibit significant spectral shifts and sign inversion, enabling highly sensitive sensing applications.
Area of Science:
- Nanophotonics
- Metamaterials
- Chirality
Background:
- Ultrathin active chiral metamaterials offer dynamic tunability for optical devices.
- Controlling near-field coupling is key to enhancing chiroptical responses.
Purpose of the Study:
- To develop ultrathin active chiral metamaterials with tunable chiroptical responses.
- To exploit these metamaterials as ultrasensitive sensors for trace solvent impurities.
Main Methods:
- Design and simulation of moiré chiral metamaterials (MCMs) with tunable near-field coupling.
- Incorporation of silk fibroin thin films as solvent-responsive spacer layers.
- Experimental characterization of chiroptical responses and sensing capabilities.
Main Results:
- Demonstrated spacer-dependent near-field coupling significantly altering circular dichroism (CD) spectra.
- Achieved active tuning of chiroptical responses, including spectral shift and sign inversion, in ultrathin MCMs.
- Developed MCMs as ultrasensitive sensors detecting impurities down to 200 ppm with ultrahigh sensitivity (>10^5 nm/RIU).
Conclusions:
- Ultrathin active chiral metamaterials with tunable near-field coupling offer dynamic control over optical chirality.
- Silk-MCMs serve as highly sensitive and responsive platforms for trace impurity detection.
- The developed metamaterials pave the way for advanced optical sensors, modulators, and switches.
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