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arXiv · 1108.4611

Geometric phase contribution to quantum non-equilibrium many-body dynamics

Michael Tomka·Anatoli Polkovnikov·Vladimir Gritsev
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Abstract

We study the influence of geometry of quantum systems underlying space of states on its quantum many-body dynamics. We observe an interplay between dynamical and topological ingredients of quantum non-equilibrium dynamics revealed by the geometrical structure of the quantum space of states. As a primary example we use the anisotropic XY ring in a transverse magnetic field with an additional time-dependent flux. In particular, if the flux insertion is slow, non-adiabatic transitions in the dynamics are dominated by the dynamical phase. In the opposite limit geometric phase strongly affects transition probabilities. We show that this interplay can lead to a non-equilibrium phase transition between these two regimes. We also analyze the effect of geometric phase on defect generation during crossing a quantum critical point.

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Michael Tomka, Anatoli Polkovnikov, Vladimir Gritsev. 2012-01-12. Geometric phase contribution to quantum non-equilibrium many-body dynamics. https://doi.org/10.1103/physrevlett.108.080404

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