Quantum superadditivity in linear optics networks: sending bits via multiple access Gaussian channels

Abstract

We study classical capacity regions of quantum Gaussian multiple access channels (MAC). In classical variants of such channels, whilst some capacity superadditivity-type effects such as the so called {\it water filling effect} may be achieved, a fundamental classical additivity law can still be identified, {\it viz.} adding resources to one sender is never advantageous to other senders in sending their respective information to the receiver. Here, we show that quantum resources allows violation of this law, by providing two illustrative schemes of experimentally feasible Gaussian MACs.

4 pages, 2 figures

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Cited by in corpus (6)

• Gaussian bosonic synergy: quantum communication via realistic channels of zero quantum capacity
• The conditional entropy power inequality for Gaussian quantum states
• Quantum Dense Coding Network using Multimode Squeezed States of Light
• Purification of Gaussian maximally mixed states
• Subadditivity of the minimum output entropy and superactivation of the classical capacity of quantum multiple access channels
• Schemes of transmission of classical information via quantum channels with many senders: discrete and continuous variables cases