Time-evolution of tripartite quantum discord and entanglement under local and non-local random telegraph noise

TL;DR

This study investigates how quantum discord and entanglement evolve over time in three-qubit systems under classical random telegraph noise, revealing that GHZ states are more robust than W states, with implications for quantum information processing.

Contribution

It provides a detailed analysis of the dynamics of quantum correlations in multipartite systems under different noise conditions, highlighting the robustness of GHZ states against decoherence.

Findings

GHZ states partially preserve quantum correlations at long times under non-local noise.

W states are less robust and lose all quantum correlations under the same conditions.

Long-lived quantum correlations in GHZ states have potential applications in quantum information science.

Abstract

Few studies explored the dynamics of non-classical correlations besides entanglement in open multipartite quantum systems. Here, we address the time-evolution of quantum discord and entanglement in a model of three non-interacting qubits subject to a classical random telegraph noise in common and separated environments. Two initial entangled states of the system are examined, namely the GHZ- and W-type states. The dynamics of quantum correlations results to be strongly affected by the input configuration of the qubits, the type of the system-environment interaction, and the memory properties of the environmental noise. When the qubits are non-locally coupled to the random telegraph noise, the GHZ-type states partially preserve, at long times, both discord and entanglement, regardless the correlation time of the environmental noise. The survived entangled states turn out to be also detectable by means of suitable entanglement witnesses. On the other hand, in the same conditions, the decohering effects suppress all the quantum correlation of the W-type states which are thus less robust than the GHZ-type ones. The long-time survival of tripartite discord and entanglement opens interesting perspectives in the use of multipartite entangled states for practical applications in quantum information science.