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arXiv · 2308.07672

Penning micro-trap for quantum computing

Abstract

Trapped ions in radio-frequency traps are among the leading approaches for realizing quantum computers, due to high-fidelity quantum gates and long coherence times. However, the use of radio-frequencies presents a number of challenges to scaling, including requiring compatibility of chips with high voltages, managing power dissipation and restricting transport and placement of ions. By replacing the radio-frequency field with a 3 T magnetic field, we here realize a micro-fabricated Penning ion trap which removes these restrictions. We demonstrate full quantum control of an ion in this setting, as well as the ability to transport the ion arbitrarily in the trapping plane above the chip. This unique feature of the Penning micro-trap approach opens up a modification of the Quantum CCD architecture with improved connectivity and flexibility, facilitating the realization of large-scale trapped-ion quantum computing, quantum simulation and quantum sensing.

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Shreyans Jain, Tobias Sägesser, Pavel Hrmo, Celeste Torkzaban, Martin Stadler, Robin Oswald, Chris Axline, Amado Bautista-Salvador, Christian Ospelkaus, Daniel Kienzler, Jonathan Home. 2023-08-15. Penning micro-trap for quantum computing. https://doi.org/10.1038/s41586-024-07111-x

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