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arXiv · 1612.07046

Loschmidt Echo Revivals: Critical and Noncritical

R. Jafari·Henrik Johannesson
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Abstract

A quantum phase transition is generally thought to imprint distinctive characteristics on the nonequilibrium dynamics of a closed quantum system. Specifically, the Loschmidt echo after a sudden quench to a quantum critical point $-$ measuring the time dependence of the overlap between initial and time-evolved states $-$ is expected to exhibit an accelerated relaxation followed by periodic revivals. We here introduce a new exactly solvable model, the extended Su-Schrieffer-Heeger model, the Loschmidt echo of which provides a counterexample. A parallell analysis of the quench dynamics of the three-site spin-interacting $XY$ model allows us to pinpoint the conditions under which a periodic Loschmidt revival actually appears

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BibTeXRIS

R. Jafari, Henrik Johannesson. 2017-01-05. Loschmidt Echo Revivals: Critical and Noncritical. https://doi.org/10.1103/physrevlett.118.015701

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