Topological order, entanglement, and quantum memory at finite temperature

Dalimil Mazac; Alioscia Hamma

doi:10.1016/j.aop.2012.05.004

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arXiv · 1112.0947

Topological order, entanglement, and quantum memory at finite temperature

Dalimil Mazac·Alioscia Hamma

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Abstract

We compute the topological entropy of the toric code models in arbitrary dimension at finite temperature. We find that the critical temperatures for the existence of full quantum (classical) topological entropy correspond to the confinement-deconfinement transitions in the corresponding Z_2 gauge theories. This implies that the thermal stability of topological entropy corresponds to the stability of quantum (classical) memory. The implications for the understanding of ergodicity breaking in topological phases are discussed.

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Dalimil Mazac, Alioscia Hamma. 2012-11-26. Topological order, entanglement, and quantum memory at finite temperature. https://doi.org/10.1016/j.aop.2012.05.004

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