EACN Workshop 2021 | Entanglement-assisted communication: theory and protocol design (Quntao Zhuang)

Entanglement-assisted communication: theory and protocol design

Entanglement offers substantial advantages in quantum information processing, but loss and noise hinder its application in practical scenarios. Although it has been well known for decades that the classical communication capacity of lossy and noisy bosonic channels can be significantly enhanced by entanglement, no practical encoding and decoding schemes are available to realize any entanglement-enabled advantage.

In this talk, we will present the theory and protocol design of entanglement-assisted classical communication. Our first result is a capacity theorem of entanglement-assisted classical communication for multiple-access channels (MAC), where we show that the capacity region enjoys a similar advantage to the known single-sender case. Then we provide structured encoding and decoding schemes for to achieve entanglement advantage in both the single-sender case and the MAC case. The protocol design has recently led to the first experimental demonstration of entanglement-assisted communication surpassing the ultimate classical capacity. We also discuss how the absence of a shared phase reference will affect the entanglement advantage.

References:
Phys. Rev. Applied 13, 034029 (2020). DOI: 10.1103/PhysRevApplied.13.034029
arXiv:2010.11974 (2020), to appear on Phys. Rev. Lett.
arXiv:2101.07482 (2021)
arXiv:2101.12173 (2021)

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