Scalable, High-Fidelity All-Electronic Control of Trapped-Ion Qubits

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. We implement electronic single-qubit gates with fidelities <a:math xmlns:a="http://www.w3.org/1998/Math/MathML" display="inline"><a:mo>≥</a:mo><a:mn>99.99912</a:mn><a:mo stretchy="false">(</a:mo><a:mn>8</a:mn><a:mo stretchy="false">)</a:mo><a:mi mathvariant="normal">%</a:mi></a:math> and demonstrate consistent performance with low crosstalk across the device. We also electronically generate two-qubit maximally entangled states with <f:math xmlns:f="http://www.w3.org/1998/Math/MathML" display="inline"><f:mn>99.97</f:mn><f:mo stretchy="false">(</f:mo><f:mn>1</f:mn><f:mo stretchy="false">)</f:mo><f:mi mathvariant="normal">%</f:mi></f:math> fidelity and long-term stable performance over continuous system operation. These state-of-the-art results highlight the potential of our all-electronic approach for coherent control of trapped-ion qubits in large-scale quantum computers.