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Scaling at the chaos threshold in an interacting quantum dot

X. Leyronas·P. G. Silvestrov·C. W. J. Beenakker
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Abstract

The chaotic mixing by random two-body interactions of many-electron Fock states in a confined geometry is investigated numerically and compared with analytical predictions. Two distinct regimes are found in the dependence of the inverse participation ratio in Fock space I on the dimensionless conductance of the quantum dot g and the excitation energy E. In both regimes I>>1, but only the small-g regime is described by the golden rule. The crossover region is characterized by a maximum in a scaling function that becomes more pronounced with increasing excitation energy. The scaling parameter that governs the transition is (E/g)ln g.

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X. Leyronas, P. G. Silvestrov, C. W. J. Beenakker. 1999-11-29. Scaling at the chaos threshold in an interacting quantum dot. https://doi.org/10.1103/physrevlett.84.3414

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