Quasi Normal Modes in Dispersive Photonic Time-Crystals
Optics
2025-10-15 v1
Abstract
Quasinormal modes characterise the transient response of static optical cavities. Here, we introduce the notion of a Floquet quasinormal mode to describe transient responses in photonic time crystals. Contrasting their static counterparts, exceptional points associated with symmetry transitions are an inherent feature, as modes spontaneously and non-perturbatively lock their phase to the oscillations of the material. We further investigate the limiting behaviour of the Floquet quasinormal modes in large cavities. Distinct non-perturbative behaviour arises in time-modulated systems as increasingly large time-crystal cavities come closer to achieving the maximum gain predicted from a bulk wavenumber bandgap.
Cite
@article{arxiv.2510.12438,
title = {Quasi Normal Modes in Dispersive Photonic Time-Crystals},
author = {Calvin M. Hooper and Ian R. Hooper and Simon A. R. Horsley},
journal= {arXiv preprint arXiv:2510.12438},
year = {2025}
}