Optical-acoustical interaction in FPU-chains with alternating large masses (plus appendix)

Roelof Bruggeman; Ferdinand Verhulst

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arXiv · 2004.03876

Optical-acoustical interaction in FPU-chains with alternating large masses (plus appendix)

Roelof Bruggeman·Ferdinand Verhulst

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Abstract

One of the problems of periodic FPU-chains with alternating masses is whether significant interactions exist between the so-called (high frequency) optical and (low frequency) acoustical groups. We show that for $\alpha$-chains with $4n$ and $8n$ particles ($n= 1, 2, \ldots$) we have significant interactions caused by external forcing. For $\beta$-chains with $4$ and $8$ particles the interactions are characterised by parametric forcing, the interactions are negligible.

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BibTeX RIS

Roelof Bruggeman, Ferdinand Verhulst. 2020-04-08. Optical-acoustical interaction in FPU-chains with alternating large masses (plus appendix). https://arxiv.org/abs/2004.03876

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