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arXiv · 0808.3874

Delocalization-Localization Transition due to Anharmonicity

D. Hajnal·R. Schilling
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Abstract

Analytical and numerical calculations for a reduced Fermi-Pasta-Ulam chain demonstrate that energy localization does not require more than one conserved quantity. Clear evidence for the existence of a sharp delocalization-localization transition at a critical amplitude is given. Approaching the critical amplitude from above and below, diverging time scales occur. Above the critical amplitude, the energy packet converges towards a discrete breather. Nevertheless, ballistic energy transportation is present, demonstrating that its existence does not necessarily imply delocalization.

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D. Hajnal, R. Schilling. 2008-08-28. Delocalization-Localization Transition due to Anharmonicity. https://doi.org/10.1103/physrevlett.101.124101

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