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arXiv · 1312.6368

One-step achievement of robust multipartite Greenberger-Horne-Zeilinger state and controlled-phase gate via Rydberg interaction

Xiao-Qiang Shao·Tai-Yu Zheng·C. H. Oh·Shou Zhang
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Abstract

We present a proposal for generation of a robust tripartite Greenberger-Horne-Zeilinger state among three-individual neutral Rydberg atoms. By modulating the relation between two-photon detuning and Rydberg interaction strength $U_{ij}(r)$, an effective Raman coupling is obtained between the hyperfine ground states $|F=2,M=2\rangle$ of three $^{87}$Rb atoms and the Rydberg states $|rrr\rangle$ via the third-order perturbation theory. This method is also capable of implementing a three-qubit controlled-phase gate with each qubit encoded into the hyperfine ground states $|F=1,M=1\rangle$ and $|F=2,M=2\rangle$. As an extension, we generalize our scheme to the case of multipartite GHZ state and quantum gate in virtue of high-order perturbation theory.

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Xiao-Qiang Shao, Tai-Yu Zheng, C. H. Oh, Shou Zhang. 2013-12-22. One-step achievement of robust multipartite Greenberger-Horne-Zeilinger state and controlled-phase gate via Rydberg interaction. https://doi.org/10.1364/josab.31.000827

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