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arXiv · 1308.5640

Quantum criticality and dynamical instability in the kicked top

V. M. Bastidas·P. Perez-Fernandez·M. Vogl·T. Brandes
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Abstract

We investigate precursors of critical behavior in the quasienergy spectrum due to the dynamical instability in the kicked top. Using a semiclassical approach, we analytically obtain a logarithmic divergence in the density of states, which is analogous to a continuous excited state quantum phase transition in undriven systems. We propose a protocol to observe the cusp behavior of the magnetization close to the critical quasienergy.

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V. M. Bastidas, P. Perez-Fernandez, M. Vogl, T. Brandes. 2014-04-22. Quantum criticality and dynamical instability in the kicked top. https://doi.org/10.1103/physrevlett.112.140408

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