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arXiv · 1103.4710

Non-equilibrium phase transition in a periodically driven XY spin chain

Tomaz Prosen·Enej Ilievski
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Abstract

We present a general formulation of Floquet states of periodically time-dependent open Markovian quasi-free fermionic many-body systems in terms of a discrete Lyapunov equation. Illustrating the technique, we analyze periodically kicekd XY spin 1/2 chain which is coupled to a pair of Lindblad reservoirs at its ends. A complex phase diagram is reported with re-entrant phases of long range and exponentially decaying spin-spin correlations as some of the system's parameters are varied. The structure of phase diagram is reproduced in terms of counting non-trivial stationary points of Floquet quasi-particle dispersion relation.

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Tomaz Prosen, Enej Ilievski. 2011-08-08. Non-equilibrium phase transition in a periodically driven XY spin chain. https://doi.org/10.1103/physrevlett.107.060403

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