Modal expansion of optical far-field quantities using quasinormal modes

Felix Binkowski,Martin Hammerschmidt,Lin Zschiedrich,Fridtjof Betz,Sven Burger,Rémi Colom,H Michinel,O Frazao,M.F Costa

doi:10.1051/epjconf/202023805007

Abstract

We discuss an approach for modal expansion of optical far-field quantities based on quasinormal modes (QNMs). The issue of the exponential divergence of QNMs is circumvented by contour integration of the far-field quantities involving resonance poles with negative and positive imaginary parts. A numerical realization of the approach is demonstrated by convergence studies for a nanophotonic system.

Highlights

For the study of physical phenomena in nano-optical systems, a modal description is the most instructive approach
We discuss an approach for modal expansion of optical far-field quantities based on quasinormal modes (QNMs)
The issue of the exponential divergence of QNMs is circumvented by contour integration of the far-field quantities involving resonance poles with negative and positive imaginary parts

Summary

Introduction

For the study of physical phenomena in nano-optical systems, a modal description is the most instructive approach. We discuss an approach for modal expansion of optical far-field quantities based on quasinormal modes (QNMs). The issue of the exponential divergence of QNMs is circumvented by contour integration of the far-field quantities involving resonance poles with negative and positive imaginary parts.

Results

Conclusion