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arXiv · 1407.6798

Noiseless Linear Amplification and Quantum Channels

Rémi Blandino·Marco Barbieri·Philippe Grangier·Rosa Tualle-Brouri
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Abstract

The employ of a noiseless linear amplifier (NLA) has been proven as a useful tool for mitigating imperfections in quantum channels. Its analysis is usually conducted within specific frameworks, for which the set of input states for a given protocol is fixed. Here we obtain a more general description by showing that a noisy and lossy Gaussian channel followed by a NLA has a general description in terms of effective channels. This has the advantage of offering a simpler mathematical description, best suitable for mixed states, both Gaussian and non-Gaussian. We investigate the main properties of this effective system, and illustrate its potential by applying it to loss compensation and reduction of phase uncertainty.

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Rémi Blandino, Marco Barbieri, Philippe Grangier, Rosa Tualle-Brouri. 2014-07-28. Noiseless Linear Amplification and Quantum Channels. https://doi.org/10.1103/physreva.91.062305

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