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arXiv · 2107.10374

Generation of a maximally entangled state using collective optical pumping

M. Malinowski·C. Zhang·V. Negnevitsky·I. Rojkov·F. Reiter·T. -L. Nguyen·M. Stadler·D. Kienzler·K. K. Mehta·J. P. Home
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Abstract

We propose and implement a novel scheme for dissipatively pumping two qubits into a singlet Bell state. The method relies on a process of collective optical pumping to an excited level, to which all states apart from the singlet are coupled. We apply the method to deterministically entangle two trapped ${}^{40}\text{Ca}^+$ ions with a fidelity of $93(1)\%$. We theoretically analyze the performance and error susceptibility of the scheme and find it to be insensitive to a large class of experimentally relevant noise sources.

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M. Malinowski, C. Zhang, V. Negnevitsky, I. Rojkov, F. Reiter, T. -L. Nguyen, M. Stadler, D. Kienzler, K. K. Mehta, J. P. Home. 2021-07-21. Generation of a maximally entangled state using collective optical pumping. https://doi.org/10.1103/physrevlett.128.080503

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