Fidelity of Gaussian channels

Carlton M. Caves; Krzysztof Wodkiewicz

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Fidelity of Gaussian channels

Carlton M. Caves·Krzysztof Wodkiewicz

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Abstract

A noisy Gaussian channel is defined as a channel in which an input field mode is subjected to random Gaussian displacements in phase space. We introduce the quantum fidelity of a Gaussian channel for pure and mixed input states, and we derive a universal scaling law of the fidelity for pure initial states. We also find the maximum fidelity of a Gaussian channel over all input states. Quantum cloning and continuous-variable teleportation are presented as physical examples of Gaussian channels to which the fidelity results can be applied.

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Carlton M. Caves, Krzysztof Wodkiewicz. 2004-09-10. Fidelity of Gaussian channels. https://arxiv.org/abs/quant-ph/0409063

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