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arXiv · 2411.13905

The transfer of nonlocality between two- and three-qubit dissipative systems with counter-rotating-wave terms

Zi-Yu Xiong·Yong-Jun Xiao·Ye-Qi Zhang·Qi-Liang He
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Abstract

We investigate the effect of counter-rotating-wave terms on nonlocality and entanglement for three qubits coupled with a common bath for strong and ultrastrong coupling regimes beyond the traditional treatment of Born-Markovian, perturbative and rotating wave approximations by employing the numerical hierarchical equations of motion approach. Our findings are as follows: (i) In the strong coupling regime, the counter-rotating terms accelerate the decay of genuine three-party correlations, and the obvious sudden birth of BN is found; (ii) In the ultrastrong coupling regime, we observe a novel phenomenon where nonlocality is consistently transferred between a three-qubit and its subsystem. Besides, the inclusion of counter-rotating wave terms obviously enhances genuine tripartite nonlocality; and (iii) These counter-rotating terms cannot effectively generate genuine three-party correlations in zero-excitation cases, which differs from previous studies involving only two qubits.

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Zi-Yu Xiong, Yong-Jun Xiao, Ye-Qi Zhang, Qi-Liang He. 2024-11-21. The transfer of nonlocality between two- and three-qubit dissipative systems with counter-rotating-wave terms. https://doi.org/10.1103/physreva.111.042410

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