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arXiv · 1012.3111

Collective versus Single--Particle Motion in Quantum Many--Body Systems: Spreading and its Semiclassical Interpretation

Jens Hammerling·Boris Gutkin·Thomas Guhr
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Abstract

We study the interplay between collective and incoherent single-particle motion in a model of two chains of particles whose interaction comprises a non-integrable part. In the perturbative regime, but for a general form of the interaction, we calculate the spectral density for collective excitations. We obtain the remarkable result that it always has a unique semiclassical interpretation. We show this by a proper renormalization procedure which allows us to map our system to a Caldeira-Leggett--type of model in which the bath is part of the system.

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Jens Hammerling, Boris Gutkin, Thomas Guhr. 2010-12-14. Collective versus Single--Particle Motion in Quantum Many--Body Systems: Spreading and its Semiclassical Interpretation. https://doi.org/10.1209/0295-5075%2F96%2F20007

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