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arXiv · 2103.09569

Estimating Quantum and Private capacities of Gaussian channels via degradable extensions

Marco Fanizza·Farzad Kianvash·Vittorio Giovannetti
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Abstract

We present upper bounds on the quantum and private capacity of single-mode, phase-insentitive Bosonic Gaussian Channels based on degradable extensions. Our findings are state-of-the-art in the following parameter regions: low temperature and high transmissivity for the thermal attenuator, low temperature for additive Gaussian noise, high temperature and intermediate amplification for the thermal amplifier.

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Marco Fanizza, Farzad Kianvash, Vittorio Giovannetti. 2021-07-21. Estimating Quantum and Private capacities of Gaussian channels via degradable extensions. https://doi.org/10.1103/physrevlett.127.210501

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