Effects of symmetry-breaking on electromagnetic backscattering
Mohamed Ismail Abdelrahman1,2,3, Evgeniia Slivina4,5, Carsten Rockstuhl1,4
1Institute of Theoretical Solid State Physics, Karlsruhe Institute of Technology, 76131, Karlsruhe, Germany.
Scientific Reports
|January 19, 2021
Summary
Breaking rotational or electromagnetic duality symmetry in certain systems increases backscattering. Deliberately breaking duality symmetry can suppress backscattering in systems with limited rotational symmetry, acting as an enhanced rotational symmetry.
Area of Science:
- Electromagnetism
- Optical Physics
- Metamaterials
Background:
- Systems with discrete rotational symmetry and electromagnetic duality symmetry exhibit zero backscattering.
- The impact of breaking these symmetries on backscattering is not well-understood.
Purpose of the Study:
- Investigate the effect of perturbatively breaking rotational and electromagnetic duality symmetries on backscattering.
- Analyze backscattering from individual objects and 2D arrays.
Main Methods:
- Perturbative symmetry breaking analysis.
- Investigation of electromagnetically-small prisms and 2D arrays.
- Polarization-dependent scattering measurements.
Main Results:
- Backscattering increases with parameters that break discrete rotational or electromagnetic duality symmetry.
- The increase in backscattering from breaking one symmetry can be linked to the other symmetry.
- Almost-complete suppression of backscattering for specific polarizations is achievable by breaking duality symmetry in systems with insufficient rotational symmetry.
Conclusions:
- Breaking discrete rotational or electromagnetic duality symmetry leads to non-zero backscattering.
- Duality symmetry breaking can effectively enhance rotational symmetry for specific polarizations, enabling backscattering suppression.
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