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arXiv · 1512.01807

Many-body delocalization transition and relaxation in a quantum dot

I. V. Gornyi·A. D. Mirlin·D. G. Polyakov
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Abstract

We revisit the problem of quantum localization of many-body states in a quantum dot and the associated problem of relaxation of an excited state in a finite correlated electron system. We determine the localization threshold for the eigenstates in Fock space. We argue that the localization-delocalization transition (which manifests itself, e.g., in the statistics of many-body energy levels) becomes sharp in the limit of a large dimensionless conductance (or, equivalently, in the limit of weak interaction). We also analyze the temporal relaxation of quantum states of various types (a "hot-electron state", a "typical" many-body state, and a single-electron excitation added to a "thermal state") with energies below, at, and above the transition.

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I. V. Gornyi, A. D. Mirlin, D. G. Polyakov. 2015-12-06. Many-body delocalization transition and relaxation in a quantum dot. https://doi.org/10.1103/physrevb.93.125419

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