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arXiv · 0801.1154

Teleportation fidelity as a probe of sub-Planck phase-space structure

A. J. Scott·Carlton M. Caves
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Abstract

We investigate the connection between sub-Planck structure in the Wigner function and the output fidelity of continuous-variable teleportation protocols. When the teleporting parties share a two-mode squeezed state as an entangled resource, high fidelity in the output state requires a squeezing large enough that the smallest sub-Planck structures in an input pure state are teleported faithfully. We formulate this relationship, which leads to an explicit relation between the fine-scale structure in the Wigner function and large-scale extent of the Wigner function, and we treat specific examples, including coherent, number, and random states and states produced by chaotic dynamics. We generalize the pure-state results to teleportation of mixed states.

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A. J. Scott, Carlton M. Caves. 2008-01-08. Teleportation fidelity as a probe of sub-Planck phase-space structure. https://doi.org/10.1016/j.aop.2008.01.007

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