Decoherence-assisted quantum key distribution

TL;DR

This paper introduces a decoherence-assisted quantum key distribution method that leverages controllable decoherence to enhance security and reduce eavesdropper information in the BB84 protocol, supported by theoretical and experimental results.

Contribution

It presents a novel approach to quantum key distribution that uses controllable decoherence to improve security against eavesdropping, with experimental validation.

Findings

Decoherence can be controlled to reduce eavesdropper information.

The method maintains low quantum bit error rate despite high decoherence.

Experimental results confirm the protocol's robustness against decoherence.

Abstract

We present a theoretical and experimental study of a controllable decoherence-assisted quantum key distribution scheme. Our method is based on the possibility of introducing controllable decoherence to polarization qubits using the spatial degree of freedom of light. We show that our method reduces the amount of information that an eavesdropper can obtain in the BB84 protocol under the entangling probe attack. We demonstrate experimentally that Alice and Bob can agree on a scheme to that gives low values of the quantum bit error rate, despite the presence of a large amount of decoherence in the transmission channel of the BB84 protocol.