On Tue, Aug 25, 2015 at 4:29 PM, Isaac Kim <ikim@perimeterinstitute.ca> wrote:

Please join us tomorrow 4pm in the Time room for a quantum information seminar by Kohtaro Kato.

Title: Information Theoretical Aspects of the Topological Entanglement Entropy

Abstract:

Topological entanglement entropy, which is defined as a linear combination of entropies of particular regions in a gapped system, is widely used to detect characteristic large-scale correlations in topologically ordered phases. We investigate an information-theoretical meaning of the topological entanglement entropy by analyzing another multi-partite correlation measure called irreducible correlation. The irreducible correlation, which is defined as the entropy difference between the maximum entropy state and the original ground state, quantifies the amount of information (correlation) in the particular region that is not contained in all local subregions. We show the equivalence of these two measures by constructing the maximum entropy state from information of local reduced density matrices. We further show that this equivalence implies that the topological entanglement entropy quantifies multipartite correlations characterizing the secret rate of a particular class of secret sharing protocols.