Instabilities and relaxation to equilibrium in long-range oscillator chains

George Miloshevich 1, 2 Jean-Pierre Nguenang Thierry Dauxois 3 Ramaz Khomeriki 4, 2 Stefano Ruffo 5
1 Department of Physics
2 Department of Physics
3 Phys-ENS - Laboratoire de Physique de l'ENS Lyon
4 MPIPKS
5 Dipartimento di Fisica e Astronomia [Firenze]
Abstract : We study instabilities and relaxation to equilibrium in a long-range extension of the Fermi-Pasta-Ulam-Tsingou (FPU) oscillator chain by exciting initially the lowest Fourier mode. Localization in mode space is stronger for the long-range FPU model. This allows us to uncover the sporadic nature of instabilities, i.e., by varying initially the excitation amplitude of the lowest mode, which is the control parameter, instabilities occur in narrow amplitude intervals. Only for sufficiently large values of the amplitude, the system enters a permanently unstable regime. These findings also clarify the long-standing problem of the relaxation to equilibrium in the short-range FPU model. Because of the weaker localization in mode space of this latter model, the transfer of energy is retarded and relaxation occurs on a much longer time-scale.
Document type :
Journal articles
Complete list of metadatas
https://hal-ens-lyon.archives-ouvertes.fr/ensl-01136811
Contributor : Thierry Dauxois <>
Submitted on : Saturday, March 28, 2015 - 7:20:59 PM
Last modification on : Saturday, November 23, 2019 - 5:42:02 PM

Links full text

arxiv

Identifiers

Collections

ENS-LYON | CNRS | UNIV-LYON1 | UDL

Citation

George Miloshevich, Jean-Pierre Nguenang, Thierry Dauxois, Ramaz Khomeriki, Stefano Ruffo. Instabilities and relaxation to equilibrium in long-range oscillator chains. Physical Review E : Statistical, Nonlinear, and Soft Matter Physics, American Physical Society, 2015, 91, pp.032927. ⟨10.1103/PhysRevE.91.032927⟩. ⟨ensl-01136811⟩

Export

BibTeX TEI DC DCterms EndNote

Share

Metrics

Record views

101

Contact

CCSD