Quantum Keyless Private Communication under intense background noise

TL;DR

This paper demonstrates practical quantum keyless private communication using polarization encoding, validated through experiments, and highlights its advantages for daylight operation, paving the way for scalable quantum communication systems.

Contribution

It introduces a polarization-multiplexed quantum keyless communication scheme and experimentally validates its effectiveness under intense background noise.

Findings

Polarization-multiplexed scheme performs well in daylight conditions

Experimental validation of on-off keying and polarization-multiplexed methods

Potential for space-based quantum communication applications

Abstract

Quantum key distribution relies on quantum mechanics to securely distribute cryptographic keys, offering security but necessitating complex infrastructure and significant resources for practical implementation. Quantum keyless private communication ensures information-theoretic security in free-space communication, with simpler setups, and without the need for secret keys by leveraging the wiretap channel model. Here we propose a variant of quantum keyless private communication using polarization encoding and experimentally validate both the original on-off keying method and the polarization-multiplexed approach using time-multiplexed threshold single-photon detectors as photon counting detectors. Our analysis highlights the advantages of polarization-multiplexed schemes for daylight operation. This work paves the way towards practical and scalable quantum communication systems, with potential applications extending to space-based communication.