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arXiv · 0910.0255

Quench dynamics as a probe of quantum criticality

R. A. Barankov
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Abstract

Quantum critical points of many-body systems can be characterized by studying response of the ground-state wave function to the change of the external parameter, encoded in the ground-state fidelity susceptibility. This quantity characterizes the quench dynamics induced by sudden change of the parameter. In this framework, I analyze scaling relations concerning the probability of excitation and the excitation energy, with the quench amplitude of this parameter. These results are illustrated in the case of one-dimensional sine-Gordon model.

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R. A. Barankov. 2009-10-02. Quench dynamics as a probe of quantum criticality. https://arxiv.org/abs/0910.0255

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