Information leakage resistant quantum dialogue against collective noise

TL;DR

This paper introduces two quantum dialogue protocols resistant to information leakage over collective noise channels, utilizing decoherence-free subspaces and simple single-photon measurements for secure, noise-free communication.

Contribution

The paper presents novel quantum dialogue protocols that are resistant to information leakage and collective noise, using decoherence-free subspaces and simplified measurement techniques.

Findings

Protocols effectively resist various active attacks.

Decoherence-free subspaces mitigate collective noise effects.

Single-photon measurements simplify implementation.

Abstract

In this paper, two information leakage resistant quantum dialogue (QD) protocols over a collective-noise channel are proposed. Decoherence-free subspace (DFS) is used to erase the influence from two kinds of collective noise, i.e., collective-dephasing noise and collective-rotation noise, where each logical qubit is composed of two physical qubits and free from noise. In each of the two proposed protocols, the secret messages are encoded on the initial logical qubits via two composite unitary operations. Moreover, the single-photon measurements rather than the Bell-state measurements or the more complicated measurements are needed for decoding, making the two proposed protocols easier to implement. The initial state of each logical qubit is privately shared between the two authenticated users through the direct transmission of its auxiliary counterpart. Consequently, the information leakage problem is avoided in the two proposed protocols. Moreover, the detailed security analysis also shows that Eve's several famous active attacks can be effectively overcome, such as the Trojan horse attack, the intercept-resend attack, the measure-resend attack, the entangle-measure attack and the correlation-elicitation (CE) attack.