Quasinormal mode expansion of optical far-field quantities
Optics
2020-07-31 v2 Computational Physics
Abstract
Quasinormal mode (QNM) expansion is a popular tool to analyze light-matter interaction in nanoresonators. However, expanding far-field quantities such as the energy flux is an open problem because QNMs diverge with an increasing distance to the resonant systems. We introduce a theory to compute modal expansions of far-field quantities rigorously. The presented approach is based on the complex eigenfrequencies of QNMs. The divergence problem is circumvented by using contour integration with an analytical continuation of the far-field quantity into the complex frequency plane. We demonstrate the approach by computing the angular resolved modal energy flux in the far field of a nanophotonic device.
Cite
@article{arxiv.2003.11305,
title = {Quasinormal mode expansion of optical far-field quantities},
author = {Felix Binkowski and Fridtjof Betz and Rémi Colom and Martin Hammerschmidt and Lin Zschiedrich and Sven Burger},
journal= {arXiv preprint arXiv:2003.11305},
year = {2020}
}