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arXiv · 1908.06101

Parallel implementation of high-fidelity multi-qubit gates with neutral atoms

Harry Levine·Alexander Keesling·Giulia Semeghini·Ahmed Omran·Tout T. Wang·Sepehr Ebadi·Hannes Bernien·Markus Greiner·Vladan Vuletić·Hannes Pichler·Mikhail D. Lukin
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Abstract

We report the implementation of universal two- and three-qubit entangling gates on neutral atom qubits encoded in long-lived hyperfine ground states. The gates are mediated by excitation to strongly interacting Rydberg states, and are implemented in parallel on several clusters of atoms in a one-dimensional array of optical tweezers. Specifically, we realize the controlled-phase gate, enacted by a novel, fast protocol involving only global coupling of two qubits to Rydberg states. We benchmark this operation by preparing Bell states with fidelity $\mathcal{F} \ge 95.0(2)\%$, and extract gate fidelity $\ge 97.4(3)\%,$ averaged across five atom pairs. In addition, we report a proof-of-principle implementation of the three-qubit Toffoli gate, in which two control atoms simultaneously constrain the behavior of one target atom. These experiments demonstrate key ingredients for high-fidelity quantum information processing in a scalable neutral atom platform.

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Harry Levine, Alexander Keesling, Giulia Semeghini, Ahmed Omran, Tout T. Wang, Sepehr Ebadi, Hannes Bernien, Markus Greiner, Vladan Vuletić, Hannes Pichler, Mikhail D. Lukin. 2019-08-16. Parallel implementation of high-fidelity multi-qubit gates with neutral atoms. https://doi.org/10.1103/physrevlett.123.170503

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