Far-field analysis of axially symmetric three-dimensional directional cloaks

• Published in: Optics express Vol. 21; no. 8; pp. 9397 - 9406
• Main Authors: Ciracì, Cristian, Urzhumov, Yaroslav, Smith, David R
• Format: Journal Article
• Language: English
• Published: United States 22-04-2013
• Subjects: Computer Simulation; Light; Models, Theoretical; Refractometry - methods; Scattering, Radiation; Surface Plasmon Resonance - methods
• ISSN: 1094-4087; 1094-4087
• DOI: 10.1364/OE.21.009397

Axisymmetric radiating and scattering structures whose rotational invariance is broken by non-axisymmetric excitations present an important class of problems in electromagnetics. For such problems, a cylindrical wave decomposition formalism can be used to efficiently obtain numerical solutions to the full-wave frequency-domain problem. Often, the far-field, or Fraunhofer region is of particular interest in scattering cross-section and radiation pattern calculations; yet, it is usually impractical to compute full-wave solutions for this region. Here, we propose a generalization of the Stratton-Chu far-field integral adapted for 2.5D formalism. The integration over a closed, axially symmetric surface is analytically reduced to a line integral on a meridional plane. We benchmark this computational technique by comparing it with analytical Mie solutions for a plasmonic nanoparticle, and apply it to the design of a three-dimensional polarization-insensitive cloak.