Disorder overtakes Order in Information Concentration over Quantum Networks

Physical Review A (Impact Factor: 3.04). 06/2011; 84(4). DOI: 10.1103/PhysRevA.84.042334
Source: arXiv

ABSTRACT We consider different classes of quenched disordered quantum XY spin chains,
including quantum XY spin glass and quantum XY model with a random transverse
field, and investigate the behavior of genuine multiparty entanglement in the
ground states of these models. We find that there are distinct ranges of the
disorder parameter that gives rise to a higher genuine multiparty entanglement
than in the corresponding systems without disorder -- an order-from-disorder in
genuine multiparty entanglement. Moreover, we show that such a disorder-induced
advantage in the genuine multiparty entanglement is useful -- it is almost
certainly accompanied by a order-from-disorder for a multiport quantum dense
coding capacity with the same ground state used as a multiport quantum network.

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