Probing multipartite entanglement, coherence and quantum information preservation under classical Ornstein-Uhlenbeck noise

TL;DR

This paper investigates how classical Ornstein-Uhlenbeck noise affects entanglement, coherence, and information preservation in four-qubit systems, highlighting the importance of coherence over entanglement and identifying conditions for long-term quantum information storage.

Contribution

It provides a detailed analysis of multipartite quantum systems under Ornstein-Uhlenbeck noise, revealing the dominance of coherence in information preservation and offering insights for optimizing classical environments in quantum computing.

Findings

Quantum information preservation depends more on coherence than entanglement.

Increasing environments accelerates quantum decay.

GHZ states show potential for long-term information storage.

Abstract

We address entanglement, coherence, and information protection in a system of four non-interacting qubits coupled with different classical environments, namely: common, bipartite, tripartite, and independent environments described by Ornstein-Uhlenbeck (ORU) noise. We show that quantum information preserved by the four qubit state is more dependent on the coherence than the entanglement using time-dependent entanglement witness, purity, and Shannon entropy. We find these two quantum phenomena directly interrelated and highly vulnerable in environments with ORU noise, resulting in the pure exponential decay of a considerable amount. The current Markovian dynamical map, as well as suppression of the fluctuating character of the environments are observed to be entirely attributable to the Gaussian nature of the noise. Furthermore, the increasing number of environments are witnessed to accelerate the amount of decay. Unlike other noises, the current noise parameter's flexible range is readily exploitable, ensuring long enough preserved memory properties. The four-qubit GHZ state, besides having a large information storage potential, stands partially entangled and coherent in common environments for an indefinite duration. Thus, it appeared to be a more promising resource for functional quantum computing than bipartite and tripartite quantum systems. In addition, we derive computational values for each system-environment interaction, which will help quantum practitioners to optimize the related kind of classical environments.