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arXiv · 1902.07028

Integrated $^{9}$Be$^{+}$ multi-qubit gate device for the ion-trap quantum computer

Henning Hahn·Giorgio Zarantonello·Marius Schulte·Amado Bautista-Salvador·Klemens Hammerer·Christian Ospelkaus
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Abstract

We demonstrate the experimental realization of a two-qubit M{\o}lmer-S{\o}rensen gate on a magnetic field-insensitive hyperfine transition in $^9$Be$^+$ ions using microwave-near fields emitted by a single microwave conductor embedded in a surface-electrode ion trap. The design of the conductor was optimized to produce a high oscillating magnetic field gradient at the ion position. The measured gate fidelity is determined to be $98.2\pm1.2\,\%$ and is limited by technical imperfections, as is confirmed by a comprehensive numerical error analysis. The conductor design can potentially simplify the implementation of multi-qubit gates and represents a self-contained, scalable module for entangling gates within the quantum CCD architecture for an ion-trap quantum computer.

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Henning Hahn, Giorgio Zarantonello, Marius Schulte, Amado Bautista-Salvador, Klemens Hammerer, Christian Ospelkaus. 2019-02-19. Integrated $^{9}$Be$^{+}$ multi-qubit gate device for the ion-trap quantum computer. https://doi.org/10.1038/s41534-019-0184-5

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