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arXiv · 2402.12955

Robust and fast microwave-driven quantum logic for trapped-ion qubits

M. A. Weber·M. F. Gely·R. K. Hanley·T. P. Harty·A. D. Leu·C. M. Löschnauer·D. P. Nadlinger·D. M. Lucas
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Abstract

Microwave-driven logic is a promising alternative to laser control in scaling trapped-ion based quantum processors. However, such electronic gates have yet to match the speed offered by their laser-driven counterparts. Here, we implement M{\o}lmer-S{\o}rensen two-qubit gates on $^{43}\text{Ca}^+$ hyperfine clock qubits in a cryogenic ($\approx25~\text{K}$) surface trap, driven by near-field microwaves. We achieve gate durations of $154~\mu\text{s}$ (with $1.0(2)\%$ error) and $331~\mu\text{s}$ ($0.5(1)\%$ error), which approaches the performance of typical laser-driven gates. In the $331~\mu\text{s}$ gate, we demonstrate a new Walsh-modulated dynamical decoupling scheme which suppresses errors due to fluctuations in the qubit frequency as well as imperfections in the decoupling drive itself.

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M. A. Weber, M. F. Gely, R. K. Hanley, T. P. Harty, A. D. Leu, C. M. Löschnauer, D. P. Nadlinger, D. M. Lucas. 2024-02-20. Robust and fast microwave-driven quantum logic for trapped-ion qubits. https://doi.org/10.1103/physreva.110.l010601

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