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arXiv · 1810.01593

Transient and persistent particle subdiffusion in a disordered chain coupled to bosons

P. Prelovsek·J. Bonca·M. Mierzejewski
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Abstract

We consider the propagation of a single particle in a random chain, assisted by the coupling to dispersive bosons. Time evolution treated with rate equations for hopping between localized states reveals a qualitative difference between dynamics due to noninteracting bosons and hard-core bosons. In the first case the transient dynamics is subdiffusive, but multi-boson processes allow for long-time normal diffusion, while hard-core effects suppress multi-boson processes leading to persistent subdiffusive transport, consistent with numerical results for a full many-body evolution. In contrast, analogous study for a quasiperiodic potential reveals a stable long-time diffusion.

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P. Prelovsek, J. Bonca, M. Mierzejewski. 2018-10-03. Transient and persistent particle subdiffusion in a disordered chain coupled to bosons. https://doi.org/10.1103/physrevb.98.125119

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