Poles and zeros in non-Hermitian systems: Application to photonics

Fuente: arXiv
Saved in:
Bibliographic Details
Main Authors: Binkowski, Felix, Betz, Fridtjof, Colom, Rémi, Genevet, Patrice, Burger, Sven
Format: Preprint
Published: 2023
Subjects:
Online Access:
Tags: Add Tag
No Tags, Be the first to tag this record!
_version_ 1866910295716265984
author Binkowski, Felix
Betz, Fridtjof
Colom, Rémi
Genevet, Patrice
Burger, Sven
author_facet Binkowski, Felix
Betz, Fridtjof
Colom, Rémi
Genevet, Patrice
Burger, Sven
contents Resonances are essential for understanding the interactions between light and matter in photonic systems. The real frequency response of the non-Hermitian systems depends on the complex-valued resonance frequencies, which are the poles of electromagnetic response functions. The zeros of the response functions are often used for designing devices, since the zeros can be located close to the real axis, where they have significant impact on scattering properties. While methods are available to determine the locations of the poles, there is a lack of appropriate approaches to find the zeros in photonic systems. We present an approach to compute poles and zeros based on contour integration of electromagnetic quantities. This also allows to extract sensitivities with respect to geometrical or other parameters enabling efficient device design. The approach is applied to a topical example in nanophotonics, an illuminated metasurface, where the emergence of reflection zeros due to the underlying resonance poles is explored using residue-based modal expansions. The generality and simplicity of the theory allows straightforward transfer to other areas of physics. We expect that easy access to zeros will enable new computer-aided design methods in photonics and other fields.
format Preprint
id arxiv_https___arxiv_org_abs_2307_04654
institution arXiv
publishDate 2023
record_format arxiv
spellingShingle Poles and zeros in non-Hermitian systems: Application to photonics
Binkowski, Felix
Betz, Fridtjof
Colom, Rémi
Genevet, Patrice
Burger, Sven
Optics
Mesoscale and Nanoscale Physics
Computational Physics
Resonances are essential for understanding the interactions between light and matter in photonic systems. The real frequency response of the non-Hermitian systems depends on the complex-valued resonance frequencies, which are the poles of electromagnetic response functions. The zeros of the response functions are often used for designing devices, since the zeros can be located close to the real axis, where they have significant impact on scattering properties. While methods are available to determine the locations of the poles, there is a lack of appropriate approaches to find the zeros in photonic systems. We present an approach to compute poles and zeros based on contour integration of electromagnetic quantities. This also allows to extract sensitivities with respect to geometrical or other parameters enabling efficient device design. The approach is applied to a topical example in nanophotonics, an illuminated metasurface, where the emergence of reflection zeros due to the underlying resonance poles is explored using residue-based modal expansions. The generality and simplicity of the theory allows straightforward transfer to other areas of physics. We expect that easy access to zeros will enable new computer-aided design methods in photonics and other fields.
title Poles and zeros in non-Hermitian systems: Application to photonics
topic Optics
Mesoscale and Nanoscale Physics
Computational Physics
url https://arxiv.org/abs/2307.04654