CoreShell Particles as Building Blocks for Systems with High Duality Symmetry
Abstract
Material electromagnetic duality symmetry requires a system to have equal electric and magnetic responses. Intrinsically dual materials that meet the duality conditions at the level of the constitutive relations do not exist in many frequency bands. Nevertheless, discrete objects like metallic helices and homogeneous dielectric spheres can be engineered to approximate the dual behavior. We exploit the extra degrees of freedom of a coreshell dielectric sphere in a particle optimization procedure. The duality symmetry of the resulting particle is more than 1 order of magnitude better than previously reported nonmagnetic objects. We use T matrixbased multiscattering techniques to show that the improvement is transferred onto the duality symmetry of composite objects when the coreshell particle is used as a building block instead of homogeneous spheres. These results are relevant for the fashioning of systems with high duality symmetry, which are required for some technologically important effects.
 Publication:

Physical Review Applied
 Pub Date:
 May 2018
 DOI:
 10.1103/PhysRevApplied.9.054051
 arXiv:
 arXiv:1711.01209
 Bibcode:
 2018PhRvP...9e4051R
 Keywords:

 Physics  Optics
 EPrint:
 5 pages, 3 figures, 1 table