International Journal of Quantum Information

Quantum discord dynamics of the GHZ state in Markovian environments

Dan Xue, Ming-Qiang Bai, Liang Tang, Si-Ting Xiong, Zhiwen Mo

Published Mar 24, 2023• 1 citation

Abstract

In quantum mechanics, quantum discord is a valuable quantum resource. As a generalization of the initial quantum discord, the multipartite quantum discord (MQD) exhibits excellent properties in the complete monogamy relation. In this paper, the dynamics of MQD are investigated for the Greenberger–Horne–Zeilinger (GHZ) state in Markovian environments. More specifically, it indicates that MQD of the GHZ state drops significantly over time in the depolarizing noise channel. Interestingly, quantum decoherence has no influence on MQD of the GHZ state in the Pauli channel [Formula: see text]. Subsequently, the analytical formulas of MQD are derived with six parameters in the Pauli channels [Formula: see text] and [Formula: see text], respectively. This is conducive to more efficient use of the GHZ state for various quantum tasks.

DOI: 10.1142/s0219749923500223

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