Asymmetric backscattering from the hybrid magneto-electric meta particle

The opticaltheorem relates the totalscattering cross-section of a givenstructure with itsforward scattering, but does not impose any restrictions on other directions. Strong backward-forward asymmetry inscattering could be achieved by exploring retarded coupling between particles, exhibiting both electric and magnetic resonances. Here, a hybrid magneto-electric particle (HMEP), consisting of a split ring resonator acting as a magnetic dipole and a wireantenna acting as an electric dipole, is shown to possess asymmetricscattering properties. When illuminated from opposite directions with the same polarization of the electric field, thestructure has exactly the sameforward scattering, whereas the backwardscattering is drastically different. Thescattering cross section is shown to be as low as zero at a narrow frequency range when illuminated from one side, while being maximal at the same frequency range when illuminated from the other side. Theoretical predictions of the phenomena are supported with both numerical and experimental conformations, obtained at the GHz frequency range, and all are in a good agreement with each other. HMEP meta-particles could be used as building blocks for variousmetamaterials assembling solar cells, invisibility cloaks, holographic masks, etc.

Source: Applied Physics Letters - November 15, 2016 Category: Physics Authors: Vitali Kozlov, Dmitry Filonov, Alexander S. Shalin, Ben Z. Steinberg and Pavel Ginzburg Source Type: research