Public and private communication with a quantum channel and a secret key

TL;DR

This paper introduces the publicly-enhanced private father protocol, which optimally combines secret keys and noisy quantum channels to generate both public and private noiseless communication, generalizing previous protocols.

Contribution

It presents a new, optimal protocol that generalizes prior work for simultaneous public and private communication over quantum channels using secret keys.

Findings

The protocol achieves optimal rates for public and private communication.

It extends previous protocols by integrating public and private information transmission.

The approach uses advanced coding techniques like random coding and piggybacking.

Abstract

We consider using a secret key and a noisy quantum channel to generate noiseless public communication and noiseless private communication. The optimal protocol for this setting is the publicly-enhanced private father protocol. This protocol exploits random coding techniques and "piggybacking" of public information along with secret-key-assisted private codes. The publicly-enhanced private father protocol is a generalization of the secret-key-assisted protocol of Hsieh, Luo, and Brun and a generelization of a protocol for simultaneous communication of public and private information suggested by Devetak and Shor.