Beyond Bounds on Light Scattering with Complex Frequency Excitations

TL;DR

This paper demonstrates that by using complex frequency excitations, it is possible to surpass traditional bounds on light scattering in nanostructures, enabling enhanced control for optical applications.

Contribution

The study introduces a novel approach of employing complex frequency excitations to exceed established scattering bounds in nanophotonics.

Findings

Surpassing traditional scattering bounds using complex frequency excitations

Achieving extreme scattering responses in nanoparticles

Potential applications in sensing, imaging, and light manipulation

Abstract

Light scattering is one of the most established wave phenomena in optics, lying at the heart of light-matter interactions and of crucial importance for nanophotonic applications. Passivity, causality and energy conservation imply strict bounds on the degree of control over scattering from small particles, with implications on the performance of many optical devices. Here, we demonstrate that these bounds can be surpassed by considering excitations at complex frequencies, yielding extreme scattering responses as tailored nanoparticles reach a quasi-steady-state regime. These mechanisms can be used to engineer light scattering of nanostructures beyond conventional limits for noninvasive sensing, imaging, and nanoscale light manipulation.