Ultra-directional super-scattering of homogenous spherical particles with radial anisotropy

TL;DR

This paper demonstrates how radial anisotropy in spherical particles can be used to achieve ultra-directional super-scattering, enabling improved nanoantenna designs for various applications.

Contribution

It introduces a method to tune electric resonances via radial anisotropy, achieving controllable overlapping of dipole resonances for directional scattering.

Findings

Radial anisotropy enables effective tuning of electric resonances.

Overlapping electric and magnetic dipoles results in unidirectional super-scattering.

Higher-order resonances can also be overlapped to further enhance directionality.

Abstract

We study the light scattering of homogenous radially-anisotropic spherical particles. It is shown that radial anisotropy can be employed to tune effectively the electric resonances, and thus enable flexible overlapping of electric and magnetic dipoles of various numbers, which leads to unidirectional forward super-scattering at different spectral positions. We further reveal that through adjusting the radial anisotropy parameters, electric and magnetic resonances of higher orders can be also made overlapped, thus further collimating the forward scattering lobes. The ultra-directional super-scattering we have obtained with individual homogenous radially anisotropic spherical particles may shed new light to the design of compact and efficient nanoantennas, which may find various applications in solar cells, bio-sensing and many other antenna based researches.