Electromagnetic interaction of arbitrary radial-dependent anisotropic spheres and improved invisibility for nonlinear-transformation-based cloaks

Abstract

An analytical method of electromagnetic wave interactions with a general radially anisotropic cloak is established. It is able to deal with arbitrary parameters (${\epsilon }_r(r)$, ${\mu }_r(r)$, ${\epsilon }_t(r)$ and ${\mu }_t(r)$) of a radially anisotropic inhomogeneous shell. The general cloaking condition is proposed from the wave relations for the first time. We derive the parameters of a novel class of spherical nonlinear cloaks and examine its invisibility performance by the proposed method at various nonlinear situations. Spherical metamaterial cloaks with improved invisibility performance is achieved with optimal nonlinearity in transformation and core-shell ratio.

19 pages, 9 figures

References in corpus (3)

• Confirmation of Cylindrical Perfect Invisibility Cloak Using Fourier-Bessel Analysis
• Cylindrical Invisibility Cloak with Simplified Material Parameters is Inherently Visible
• Extraordinary surface voltage effect in the invisibility cloak with an active device inside