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Optimized Microwave Near-Field Control in a Planar Ion Trap

Martina Carsjens, M. Kohnen, T. Dubielzig, C. Ospelkaus

Published Jan 1, 2014• 0 citations
Publisher

Abstract

We describe a microfabricated planar ion trap with integrated microwave conductors. Using numerical simulations, it has been optimized for multi-qubit operations driven by microwave near-fields and represents a considerable experimental simplification.
DOI
10.1364/cleo_at.2014.jtu4a.42

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Individual-qubit addressing is a prerequisite for many instances of quantum information processing. We demonstrate this capability on trapped-ion qubits with microwave near fields delivered by electrode structures integrated into a microfabricated surface-electrode trap. We describe four approaches that may be used in quantum information experiments with hyperfine levels as qubits. We implement individual control on two 25Mg+ ions separated by 4.3 μm and find spin-flip crosstalk errors on the order of 10(-3).
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Abstract We demonstrate the experimental realization of a two-qubit Mølmer–Sørensen 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 ± 1.2% 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.