Figure 2
From: Molding acoustic, electromagnetic and water waves with a single cloak
Numerical computation of radar cross section (RCS) for cloak and cylindrical metal obstacles versus frequency (three-dimensional electromagnetic simulations with Computer Simulation Technology Microwave Studio).
A small metallic obstacle surrounded by cloak (dashed dark blue curve) is nearly superimposed with RCS of cloak on its own (dotted green curve) and lower than RCS of small metallic obstacle (dotted red curve), which is itself smaller than RCS of large metallic obstacle of same diameter as the cloak (solid light blue curve) from 3 GHz to 7.8 GHz. Two insets further show isovalues of the real part of the longitudinal magnetic field for a plane wave incident at 3.5 GHz from the left on the small obstacle surrounded by the cloak –see inset marked with dashed blue lines—and on the small obstacle on its own –see inset with red dotted lines—, the latter displaying stronger forward scattering.
