Quantum Multiple Access Wiretap Channel: On the One-Shot Achievable Secrecy Rate Regions

TL;DR

This paper investigates the one-shot secrecy capacity of classical-quantum multiple access wiretap channels using novel decoding techniques and introduces a dual channel model to address privacy and decoding challenges.

Contribution

It introduces a new dual channel model and applies innovative decoding strategies to analyze one-shot achievable secrecy rates in quantum multi-user channels.

Findings

Developed a simultaneous position-based decoder for secure decoding.

Analyzed the CQ-MA-WTC using Sen's one-shot joint typicality lemma.

Proposed a dual channel model to address privacy and decoding issues.

Abstract

In this paper, we want to investigate classical-quantum multiple access wiretap channels (CQ-MA-WTC) under one-shot setting. In this regard, we analyze the CQ-MA-WTC using simultaneous position-based decoder for reliable decoding and using a newly introduced technique in order to decode securely. Also, for the sake of comparison, we analyze the CQ-MA-WTC using Sen's one-shot joint typicality lemma for reliable decoding. The simultaneous position-based decoder tends to a multiple hypothesis testing problem. Also, using convex splitting to analyze the privacy criteria in a simultaneous scenario becomes problematic. To overcome both problems, we first introduce a new channel that can be considered as a dual to the CQ-MA-WTC. This channel is called a point-to-point quantum wiretap channel with multiple messages (PP-QWTC). In the following, as a strategy to solve the problem, we also investigate and analyze quantum broadcast channels (QBCs) under the one-shot setting.