Fundamental Limit on the Power of Entanglement Assistance in Quantum Communication

Abstract

The optimal rate of reliable communication over a quantum channel can be enhanced by pre-shared entanglement. Whereas the enhancement may be unbounded in infinite-dimensional settings even when the input power is constrained, a long-standing conjecture asserts that the ratio between the entanglement-assisted and unassisted classical capacities is bounded in finite-dimensional settings [Bennett et al., IEEE Trans. Inf. Theory 48, 2637 (2002)]. In this work, we prove this conjecture by showing that their ratio is upper bounded by $o(d^2)$, where $d$ is the input dimension of the channel. An application to quantum communication with noisy encoders and decoders is given.

arXiv comment7 pages, 1 figure

References in corpus (11)

• Entanglement-Assisted Classical Capacity of Noisy Quantum Channels
• Covert Optical Communication
• On entanglement-assisted classical capacity
• Continuity bounds on the quantum relative entropy
• Practical route to entanglement-assisted communication over noisy bosonic channels
• Quantum Limits in Optical Communications
• Entanglement-Assisted Communication Surpassing the Ultimate Classical Capacity
• Second-Order Asymptotics for the Classical Capacity of Image-Additive Quantum Channels
• Complete entropic inequalities for quantum Markov chains
• Fault-tolerant Coding for Quantum Communication
• Fault-tolerant Coding for Entanglement-Assisted Communication

Cited by in corpus (3)

• Detecting genuine multipartite entanglement using moments of positive maps
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• Detection of nonabsolute separability in quantum states and channels through moments