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arXiv · 1803.03856

Light-cone velocities after a global quench in a non-interacting model

Khadijeh Najafi·M. A. Rajabpour·J. Viti
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Abstract

We study the light-cone velocity for global quenches in the non-interacting XY chain starting from a class of initial states that are eigenstates of the local $z$-component of the spin. We point out how translation invariance of the initial state can affect the maximal speed at which correlations spread. As a consequence the light-cone velocity can be state-dependent also for non-interacting systems: a new effect of which we provide clear numerical evidence and analytic predictions. Analogous considerations, based on numerical results, are drawn for the evolution of the entanglement entropy.

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Khadijeh Najafi, M. A. Rajabpour, J. Viti. 2018-05-03. Light-cone velocities after a global quench in a non-interacting model. https://doi.org/10.1103/physrevb.97.205103

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