Work

Quantum keyless private communication under intense background noise

Year: 2026

Type: article

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.

Source: Physical Review A

DOI: 10.1103/q269-nmbv

Authors: Pedro Neto Mendes, Davide Rusca, Hugo Zbinden, Emmanuel Zambrini Cruzeiro

Institutions: Instituto de Telecomunicações, Instituto Superior Técnico, Universidade de Vigo

Language: English

Topic: Quantum Information and Cryptography

Subfield: Artificial Intelligence

Field: Computer Science

Domain: Physical Sciences

Open Access status: green

Funders: European Commission, Ministerio de Ciencia e Innovación, Instituto de Telecomunicações, Fundação para a Ciência e a Tecnologia

Award: G7671413979