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arXiv · 0811.2527

Non-adiabacity and large flucutations in a many particle Landau Zener problem

A. Altland·V. Gurarie·T. Kriecherbauer·A. Polkovnikov
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Abstract

We consider the behavior of an interacting many particle system under slow external driving -- a many body generalization of the Landau-Zener paradigm. We find that a conspiracy of interactions and driving leads to physics profoundly different from that of the single particle limit: for practically all values of the driving rate the particle distributions in Hilbert space are very broad, a phenomenon caused by a strong amplification of quantum fluctuations in the driving process. These fluctuations are 'non-adiabatic' in that even at very slow driving it is exceedingly difficult to push the center of the distribution towards the limit of full ground state occupancy. We obtain these results by a number of complementary theoretical approaches, including diagrammatic perturbation theory, semiclassical analysis, and exact diagonalization.

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A. Altland, V. Gurarie, T. Kriecherbauer, A. Polkovnikov. 2008-11-16. Non-adiabacity and large flucutations in a many particle Landau Zener problem. https://doi.org/10.1103/physreva.79.042703

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