IEEE International Conference on Quantum Computing and Engineering (QCE)

Demonstration of a micro-fabricated Penning trap for quantum computing

Tobias Sägesser, Shreyans Jain, Pavel Hrmo, Daniel Kienzler, Jonathan Home

Published Sep 17, 2023• 0 citations

Abstract

Trapped-ion quantum information processors are among the leading candidates to realise large-scale quantum computing. In trying to scale the number of confined ions in radio-frequency (rf) traps, several challenges arise due to the use of the rf fields. Ion placement is restricted to the vicinity of the rf null in order to minimise excess micromotion. Miniaturisation of trap geometries is desirable for increased ion density, but is at odds with the need to deliver high-voltage rf and tolerate the resulting power dissipation. We demonstrate a platform based on Penning traps, where ions are radially confined using a strong magnetic field. Static electric fields are then sufficient to provide confinement along the axis. We confine a single9Be + ion in a 3 T magnetic field using a micro-fabricated trap and realise transport to arbitrary positions above the trap chip. Furthermore, we show full quantum control of the spin and motion of the trapped ion. Ground state cooling of all motional modes is achieved and we measure the rate of motional heating due to electric field noise in the absence of an rf drive, obtaining noise levels below those observed in similar rf traps. Since only static fields are required for ion confinement, we can temporarily electrically isolate the trap electrodes from technical noise using switches, further reducing the observed electric field noise.

DOI: 10.1109/qce57702.2023.10283

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