Backward superscattering engineering via mode superposition

Subwavelength particles with a total scattering cross-section exceeding the single channel limit are called super scatterers, which can provide the ability to control light at the nanoscale. Superscatters have been constructed in different regime such as electromagnetic waves, acoustic system, and water waves. Recently, various of structures for superscatterer have been proposed, but most of which are typically constructed with negligible backscattering, in sharp contrast to its significant forward scattering, which limits further applications. The mainly proven capability of superscatterer is protecting the objects behind it off scattering[3]. we examine this overlooked phenomenon in a 2D rotational symmetric system and find that this behavior can be attributed to the superposition of resonant modes in adjacent angular momentum channels. In the process, we outline a general perspective on the relationship between the forward and backward scattering and mode combinations. Specifically, we will demonstrate enhancing backscatter beyond the reach of single channel by recombining resonant modes in a simple model.