J. Mosca Toba

Scalable, high-fidelity all-electronic control of trapped-ion qubits

C. M. Löschnauer, J. Mosca Toba [1], A. C. Hughes [1], S. A. King [1], M. A. Weber [1], R. Srinivas [1,2], R. Matt [1], R. Nourshargh [1], D. T. C. Allcock [1,3], C. J. Ballance [1,2], C. Matthiesen [1], M. Malinowski [1], T. P. Harty [1]

Abstract

The central challenge of quantum computing is implementing high-fidelity quantum gates at scale. However, many existing approaches to qubit control suffer from a scale-performance trade-off, impeding progress towards the creation of useful devices. Here, we present a vision for an electronically controlled trapped-ion quantum computer that alleviates this bottleneck. Our architecture utilizes shared current-carrying traces and local tuning electrodes in a microfabricated chip to perform quantum gates with low noise and crosstalk regardless of device size. To verify our approach, we experimentally demonstrate low-noise site-selective single- and two-qubit gates in a seven-zone ion trap that can control up to 10 qubits. We implement electronic single-qubit gates with 99.99916(7)% fidelity, and demonstrate consistent performance with low crosstalk across the device. We also electronically generate two-qubit maximally entangled states with 99.97(1)% fidelity and long-term stable performance over continuous system operation. These state-of-the-art results validate the path to directly scaling these techniques to large-scale quantum computers based on electronically controlled trapped-ion qubits.