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arXiv · 0909.0752

Topological Order Following a Quantum Quench

D. I. Tsomokos·A. Hamma·W. Zhang·S. Haas·R. Fazio
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Abstract

We determine the conditions under which topological order survives a rapid quantum quench. Specifically, we consider the case where a quantum spin system is prepared in the ground state of the Toric Code Model and, after the quench, it evolves with a Hamiltonian that does not support topological order. We provide analytical results supported by numerical evidence for a variety of quench Hamiltonians. The robustness of topological order under non-equilibrium situations is tested by studying the topological entropy and a novel dynamical measure, which makes use of the similarity between partial density matrices obtained from different topological sectors.

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D. I. Tsomokos, A. Hamma, W. Zhang, S. Haas, R. Fazio. 2009-09-03. Topological Order Following a Quantum Quench. https://doi.org/10.1103/physreva.80.060302

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