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Updated: Dec 8, 2025
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Simulation, Fabrication and Characterization of THz Metamaterial Absorbers
Published on: December 27, 2012
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Active meta polarizer for terahertz frequencies
Hang Wong1, Kai Xu Wang2,3, Laure Huitema4
1State Key Laboratory of Terahertz and Millimeter Waves, Department of Electrical Engineering, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong.
Scientific Reports
|September 22, 2020
Summary
This study presents a novel active terahertz polarizer using vanadium dioxide. The device offers efficient, fast, and independently controllable polarization reconfiguration for terahertz waves.
Area of Science:
- Terahertz (THz) technology
- Metamaterials and Nanophotonics
- Phase-change materials
Background:
- Active meta-polarizers are crucial for terahertz (THz) applications like imaging and communications.
- Current adaptive control methods for meta-polarizers are often complex and rely on external stimuli.
Purpose of the Study:
- To introduce a novel active terahertz polarizer with a simple structure for dynamic polarization reconfiguration.
- To demonstrate independent manipulation of THz wave polarization in two orthogonal directions.
Main Methods:
- Fabrication of a single-layer active polarizer using vanadium dioxide (VO2) patterns integrated with a metallic patch matrix.
- Utilizing DC bias for convenient and actuator-free control of the device's polarization properties.
Main Results:
- The proposed device functions as an efficient terahertz polarizer and reflector.
- Demonstrated efficient and rapid polarization changes of THz waves over a broad bandwidth.
- Achieved independent control of polarization in two orthogonal directions.
Conclusions:
- The developed active terahertz polarizer offers high efficiency, compact size, low loss, and fast response.
- DC bias control eliminates the need for external actuators, lasers, or heaters, enhancing practicality.
- The polarizer is highly integrable for adaptive terahertz circuits and systems.
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