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arXiv · 1505.01917

Information-theoretical analysis of topological entanglement entropy and multipartite correlations

Kohtaro Kato·Fabian Furrer·Mio murao
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Abstract

A special feature of the ground state in a topologically ordered phase is the existence of large scale correlations depending only on the topology of the regions. These correlations can be detected by the topological entanglement entropy or by a measure called irreducible correlation. We show that these two measures coincide for states obeying an area law and having zero-correlation length. Moreover, we provide an operational meaning for these measures by proving its equivalence to the optimal rate of a particular class of secret sharing protocols. This establishes an information-theoretical approach to multipartite correlations in topologically ordered systems.

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Kohtaro Kato, Fabian Furrer, Mio murao. 2016-01-08. Information-theoretical analysis of topological entanglement entropy and multipartite correlations. https://doi.org/10.1103/physreva.93.022317

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