Quantum Multiple-Access One-Time Pad

TL;DR

This paper introduces the quantum multiple-access one-time pad, a protocol where multiple senders encode messages into shared quantum states, ensuring the receiver can decode while preventing eavesdroppers from gaining information, with a characterization of achievable rates.

Contribution

It provides the first single-letter characterization of the achievable rate region for the quantum multiple-access one-time pad in the asymptotic limit.

Findings

Achieves near-perfect decoding for the receiver.

Eavesdropper gains negligible information.

Defines the rate region for multiple senders in quantum communication.

Abstract

We introduce and analyze an information theoretical task that we call the quantum multiple-access one-time pad. Here, a number of senders initially share a correlated quantum state with a receiver and an eavesdropper. Each sender performs a local operation to encode a classical message and sends their system to the receiver, who subsequently performs a measurement to decode the messages. The receiver will be able to decode the messages almost perfectly, while the eavesdropper must not be able to extract information about the messages even if they have access to the quantum systems transmitted. We consider a ''conditional'' scenario in which a portion of the receiver's side information is also accessible to the eavesdropper. We investigate the maximum amount of classical information that can be encoded by each of the senders. We derive a single-letter characterization for the achievable rate region in an asymptotic limit of infinitely many copies and vanishingly small error.