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arXiv · 1610.03919

Non-equilibrium quantum phase transition via entanglement decoherence dynamics

Yu-Chen Lin·Pei-Yun Yang·Wei-Min Zhang
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Abstract

We investigate the decoherence dynamics of continuous variable entanglement as the system-environment coupling strength varies from the weak-coupling to the strong-coupling regimes. Due to the existence of localized modes in the strong-coupling regime, the system cannot approach equilibrium with its environment, which induces a nonequilibrium quantum phase transition. We analytically solve the entanglement decoherence dynamics for an arbitrary spectral density. The nonequilibrium quantum phase transition is demonstrated as the system-environment coupling strength varies for all the Ohmic-type spectral densities. The 3-D entanglement quantum phase diagram is obtained.

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Yu-Chen Lin, Pei-Yun Yang, Wei-Min Zhang. 2016-10-13. Non-equilibrium quantum phase transition via entanglement decoherence dynamics. https://doi.org/10.1038/srep34804

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