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Updated: May 8, 2026
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Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
Reflection resonance switching in metamaterial twisted nematics cell
1Department of Physics, Ewha Womans University, Seoul 120-750, South Korea.
Optics Express
|August 14, 2013
Summary
Researchers demonstrate electric switching of near-infrared reflection resonances using a novel reflective metamaterial twisted nematic liquid crystal cell, enabling dynamic control of light polarization.
Area of Science:
- Optics and Photonics
- Materials Science
- Liquid Crystal Displays
Background:
- Metamaterials offer unique optical properties through subwavelength structuring.
- Liquid crystals provide tunable optical characteristics via external stimuli.
- Controlling light polarization with reflective metamaterials is crucial for optical devices.
Purpose of the Study:
- To experimentally demonstrate electric switching of reflection resonances in a reflective metamaterial.
- To investigate the polarization-dependent optical response of the metamaterial.
- To achieve dynamic control over near-infrared light using liquid crystal technology.
Main Methods:
- Fabrication of a reflective metamaterial using nano-sized double-split ring resonator apertures via focused ion beam milling.
- Integration of the metamaterial into a twisted nematic liquid crystal cell.
- Application of an external voltage (10V) across a 12μm cell gap to induce switching.
Main Results:
- Achieved full electric switching between two orthogonal polarization-dependent reflection resonances.
- Observed distinct reflection resonances due to the two-fold rotational symmetry of the metamaterial.
- Measured switch-on and switch-off time constants in the order of 100ms and 10ms, respectively.
Conclusions:
- Electric field control of reflection resonances in metamaterial-liquid crystal hybrid devices is feasible.
- The demonstrated device offers dynamic polarization control in the near-infrared spectrum.
- The rapid switching times suggest potential for high-speed optical modulation applications.
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