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arXiv · 1808.07485

Topologically-Protected Long Edge Coherence Times in Symmetry-Broken Phases

Daniel E. Parker·Romain Vasseur·Thomas Scaffidi
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Abstract

We argue that symmetry-broken phases proximate in phase space to symmetry-protected topological phases can exhibit dynamical signatures of topological physics. This dynamical, symmetry-protected "topological" regime is characterized by anomalously long edge coherence times due to the topological decoration of quasiparticle excitations, even if the underlying zero-temperature ground state is in a non-topological, symmetry-broken state. The dramatic enhancement of coherence can even persist at infinite temperature due to prethermalization. We find exponentially long edge coherence times that are stable to symmetry-preserving perturbations, and not the result of integrability.

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Daniel E. Parker, Romain Vasseur, Thomas Scaffidi. 2018-08-22. Topologically-Protected Long Edge Coherence Times in Symmetry-Broken Phases. https://doi.org/10.1103/physrevlett.122.240605

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