Electromagnetic helicity in twisted cavity resonators
Through left- or right-handed twisting, we investigate the impact of mirror-asymmetry (chirality) of the conducting boundary conditions of an equilaterial triangular cross section electromagnetic resonator.We observe the generation of eigenmodes with nonzero electromagnetic helicity as a result of the coupling of near degenerate TE<sub>11(p+1)</sub> and TM11p modes. This can be interpreted as an emergence of magnetoelectric coupling, which in turn produces a measurable shift in resonant mode frequency as a function of twist angle. We show that this coupling mechanism is equivalent to introducing a nonzero chirality material parameter κ<sub>eff</sub> or axion field θ<sub>eff</sub> to the medium. Our findings demonstrate the potential for real-time, macroscopic manipulation of electromagnetic helicity.
Authors
- E. C. I. Paterson (ORCID: https://orcid.org/0000-0003-3752-5815)
- Michael E. Tobar (ORCID: https://orcid.org/0000-0002-3139-1994)
- Jeremy Bourhill (ORCID: https://orcid.org/0000-0002-5667-7745)
- Maxim Goryachev (ORCID: https://orcid.org/0000-0002-0257-4054)
Institutions
- The University of Western Australia (AU)
Publication Details
- Journal
- Physical review. A/Physical review, A
- Published
- 2025-06-30
- DOI
- https://doi.org/10.1103/6gp4-76td
- Citations
- 1
- Primary Topic
- Metamaterials and Metasurfaces Applications
- Type
- article
- Field-Weighted Citation Impact
- 0.43
Funders
- Australian Research Council