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arXiv · 1911.03954

Robust and resource-efficient microwave near-field entangling $^9$Be$^+$ gate

G. Zarantonello·H. Hahn·J. Morgner·M. Schulte·A. Bautista-Salvador·R. F. Werner·K. Hammerer·C. Ospelkaus
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Abstract

Microwave trapped-ion quantum logic gates avoid spontaneous emission as a fundamental source of decoherence. However, microwave two-qubit gates are still slower than laser-induced gates and hence more sensitive to fluctuations and noise of the motional mode frequency. We propose and implement amplitude-shaped gate drives to obtain resilience to such frequency changes without increasing the pulse energy per gate operation. We demonstrate the resilience by noise injection during a two-qubit entangling gate with $^9$Be$^+$ ion qubits. In absence of injected noise, amplitude modulation gives an operation infidelity in the $10^{-3}$ range.

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G. Zarantonello, H. Hahn, J. Morgner, M. Schulte, A. Bautista-Salvador, R. F. Werner, K. Hammerer, C. Ospelkaus. 2019-11-10. Robust and resource-efficient microwave near-field entangling $^9$Be$^+$ gate. https://doi.org/10.1103/physrevlett.123.260503

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