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arXiv · 2502.02344

Sub-Power Law Decay of the Wave Packet Maximum in Disordered Anharmonic Chains

Wojciech De Roeck·Lydia Giacomin·Amirali Hannani·Francois Huveneers
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Abstract

We show that the peak of an initially localized wave packet in one-dimensional nonlinear disordered chains decays more slowly than any power law of time. The systems under investigation are Klein-Gordon and nonlinear disordered Schr\"odinger-type chains, characterized by a harmonic onsite disordered potential and quartic nearest-neighbor coupling. Our results apply in the long-time limit, hold almost surely, and are valid for arbitrary finite energy values.

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Wojciech De Roeck, Lydia Giacomin, Amirali Hannani, Francois Huveneers. 2025-02-04. Sub-Power Law Decay of the Wave Packet Maximum in Disordered Anharmonic Chains. https://arxiv.org/abs/2502.02344

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