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arXiv · 1501.04083

Coherence and Rydberg blockade of atomic ensemble qubits

M. Ebert·M. Kwon·T. G. Walker·M. Saffman
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Abstract

We demonstrate $|W\rangle$ state encoding of multi-atom ensemble qubits. Using optically trapped Rb atoms the $T_2$ coherence time is 2.6(3) ms for $\bar N=7.6$ atoms and scales approximately inversely with the number of atoms. Strong Rydberg blockade between two ensemble qubits is demonstrated with a fidelity of $0.89(1)$ and a fidelity of $\sim \hspace{-.05cm}1.0$ when postselected on control ensemble excitation. These results are a significant step towards deterministic entanglement of atomic ensembles.

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M. Ebert, M. Kwon, T. G. Walker, M. Saffman. 2015-01-16. Coherence and Rydberg blockade of atomic ensemble qubits. https://doi.org/10.1103/physrevlett.115.093601

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