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arXiv · 2207.05932

Engineering steady entanglement for trapped ions at finite temperature by dissipation

Xiao-Qiang Shao
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Abstract

We propose a dissipative method for preparation of a maximally entangled steady state of two trapped ions in the Lamb-Dicke limit. By addressing the trapped-ion system with a monochromatic standing wave laser pulse of frequency resonant with the ionic transition and a microwave field coupled to the ground-state transitions, we obtain an effective coupling between two particles, which is independent of the phonon-number fluctuations. Meanwhile, the controlled spontaneous emission of trapped ions is implemented via pumping the metastable states upwards to the short-lived ionic states by an auxiliary laser field. Combining the unitary processes with the engineered dissipation, a deterministic Bell state can be produced irrespective of the initial states of systems. Moreover, our result shows that the CHSH inequality can be violated for a wide range of decoherence parameters, even at finite temperature.

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Xiao-Qiang Shao. 2022-07-13. Engineering steady entanglement for trapped ions at finite temperature by dissipation. https://doi.org/10.1103/physreva.98.042310

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