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arXiv · 2602.10898

Phonon gap analysis for equilibria of perturbed almost-periodic Frenkel-Kontorova models

Yujia An·Xifeng Su
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Abstract

For generalized Frenkel-Kontorova models subjected to almost-periodic media, employing both the KAM method and the approach of `anti-integrable' limits, two different types of equilibria are obtained in \cite{an2024kamtheoryalmostperiodicequilibria} and \cite{du2024anti} respectively. We study the phonon gap around these equilibria and we find that the KAM equilibria do not have a phonon gap but the equilibria obtained by anti-integrable limits do have.

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Yujia An, Xifeng Su. 2026-02-11. Phonon gap analysis for equilibria of perturbed almost-periodic Frenkel-Kontorova models. https://arxiv.org/abs/2602.10898

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