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arXiv · 1402.2789

Nonadiabatic stationary behaviour in a driven low-dimensional gapped system

Abstract

We discuss the emergence of nonadiabatic behavior in the dynamics of the order parameter in a low-dimensional quantum many-body system subject to a linear ramp of one of its parameters. While performing a ramp within a gapped phase seems to be the most favorable situation for adiabaticity, we show that such a change leads eventually to the disruption of the order, no matter how slowly the ramp is performed. We show this in detail by studying the dynamics of the one-dimensional quantum Ising model subject to linear variation of the transverse magnetic field within the ferromagnetic phase, and then propose a general argument applicable to other systems.

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Anna Maraga, Pietro Smacchia, Michele Fabrizio, Alessandro Silva. 2014-02-12. Nonadiabatic stationary behaviour in a driven low-dimensional gapped system. https://doi.org/10.1103/physrevb.90.041111

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