Topological winding guaranteed coherent orthogonal scattering

TL;DR

This paper introduces a topologically rooted phenomenon called coherent orthogonal scattering, where waves become orthogonal to reference states without scatterers, revealing new insights into wave control and scattering topology.

Contribution

It uncovers the topological nature of coherent orthogonal scattering, linking it to the winding number and dimension of scattering matrices, and demonstrates its implications for wave control.

Findings

Achieves unity extinction coefficient and complete mode conversion

Reveals the topological origin of orthogonal scattering phenomena

Deepens understanding of topological effects in wave scattering

Abstract

Coherent control has enabled various novel phenomena in wave scattering. We introduce an effect called coherent orthogonal scattering, where the output wave becomes orthogonal to the reference output state without scatterers. This effect leads to a unity extinction coefficient and complete mode conversion. We examine the conditions for this effect and reveal its topological nature by relating it to the indivisibility between the dimension and the winding number of scattering submatrices. These findings deepen our understanding of topological scattering phenomena.