Quantum correlations dynamics of three-qubit states coupled to an XY spin chain: Role of coupling strengths

• 来源期刊: 中国物理B（英文版）
• 关键词: quantum phase transition quantum correlation tripartite system XY spin chain
• 年，卷（期）: 2017,（10）
• 页码范围: 74-81
• 页数: 8页
• 语种: 英文
• DOI: 10.1088/1674-1056/26/10/100501

摘要

We investigate the prominent impacts of coupling strengths on the evolution of entanglement and quantum discord for a three-qubit system coupled to an XY spin-chain environment.In the case of a pure W state,more robust,even larger nonzero quantum correlations can be obtained by tailoring the coupling strengths between the qubits and the environment.For a mixed state consisting of the GHZ and W states,the dynamics of entanglement and quantum discord can characterize the critical point of quantum phase transition.Remarkably,a large nonzero quantum discord is generally retained,while the nonzero entanglement can only be obtained as the system-environment coupling satisfies certain conditions.We also find that the impact of each qubit's coupling strength on the quantum correlation dynamics strongly depends on the variation schemes of the system-environment couplings.