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Microwave modes of ambidextrous helices
J Gudge-Brooke1, N Clow2, A P Hibbins3
1Department of Physics and Astronomy, Centre for Metamaterial Research and Innovation, University of Exeter, Stocker Road, Exeter, EX4 4QL, UK. jeg219@exeter.ac.uk.
Scientific Reports
|August 19, 2025
Summary
Ambidextrous helices, with balanced left- and right-handed turns, show unique dual linear polarization modes in the gigahertz range. Geometric tuning allows independent control over electric and magnetic dipole resonances for advanced microwave devices.
Area of Science:
- Electromagnetism
- Microwave Engineering
- Materials Science
Background:
- Conventional helices support only elliptically polarized modes.
- Ambidextrous helices offer a novel approach to electromagnetic wave manipulation.
- Gigahertz frequency range applications demand advanced resonant structures.
Purpose of the Study:
- Investigate the electromagnetic properties of ambidextrous helices.
- Analyze the distinct resonant modes of these structures.
- Explore the tunability of these modes for device applications.
Main Methods:
- Numerical simulations of a four-turn ambihelix.
- Experimental validation of simulated results.
- Analysis of electric and magnetic dipole-like resonant modes.
Main Results:
- Ambidextrous helices exhibit two distinct linearly polarized resonant modes.
- These modes show electric dipole-like and magnetic dipole-like behavior.
- Resonance frequencies are independently tunable via geometric modifications, including pitch adjustment.
Conclusions:
- Geometric tuning allows frequency exchange and coincidence of the dipole modes.
- Ambidextrous helices offer potential for reconfigurable and multifunctional microwave devices.
- Dual-mode capability and geometric control enhance design flexibility for antennas, metamaterials, and polarization-sensitive applications.
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