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Teleportation fidelities of squeezed states from thermodynamical state space measures

Alessio Serafini·Oscar C. O. Dahlsten·Martin B. Plenio
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Abstract

We introduce a "microcanonical" measure (complying with the "general canonical principle") over the second moments of pure bosonic Gaussian states under an energy constraint. We determine the average fidelity for the teleportation of states distributed according to such a measure and compare it to a threshold obtained from a feasible classical strategy. Furthermore, we show that, under the proposed measure, the distribution of the entanglement concentrates around a finite value at the thermodynamical limit and, in general, the typical entanglement of Gaussian states with maximal energy E is not close to the maximum allowed by E.

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Alessio Serafini, Oscar C. O. Dahlsten, Martin B. Plenio. 2007-05-18. Teleportation fidelities of squeezed states from thermodynamical state space measures. https://doi.org/10.1103/physrevlett.98.170501

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