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arXiv · 1808.03473

Fast three-qubit Toffoli quantum gate based on the three-body F\"{o}rster resonances in Rydberg atoms

I. I. Beterov·I. N. Ashkarin·E. A. Yakshina·D. B. Tretyakov·V. M. Entin·I. I. Ryabtsev·P. Cheinet·P. Pillet·M. Saffman
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Abstract

We propose a scheme of fast three-qubit Toffoli quantum gate for ultracold neutral-atom qubits. The scheme is based on the Stark-tuned three-body F\"{o}rster resonances, which we have observed in our recent experiment [D.B.Tretyakov et al., Phys.Rev.Lett. 119, 173402 (2017)]. The three-body resonance corresponds to a transition when the three interacting atoms change their states simultaneously, and it occurs at a different dc electric field with respect to the two-body F\"{o}rster resonance. A combined effect of three-body and two-body F\"{o}rster interactions in external electric and magnetic fields near the three-body resonance results in complex coherent behavior of the populations and phases of collective states of a three-atom system. We have found that it is possible to obtain experimental conditions suitable to implement three-qubit Toffoli gate with 96.8\% fidelity and less than 3~$\mu$s duration.

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I. I. Beterov, I. N. Ashkarin, E. A. Yakshina, D. B. Tretyakov, V. M. Entin, I. I. Ryabtsev, P. Cheinet, P. Pillet, M. Saffman. 2018-08-10. Fast three-qubit Toffoli quantum gate based on the three-body F\"{o}rster resonances in Rydberg atoms. https://doi.org/10.1103/physreva.98.042704

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