Operating semiconductor quantum processors with hopping spins

• 成果类型: Article
• 署名作者: Wang, Chien-An; John, Valentin; Tidjani, Hanifa; Yu, Cecile X.; Ivlev, Alexander S.; Deprez, Corentin; van Riggelen-Doelman, Floor; Woods, Benjamin D.; Hendrickx, Nico W.; Lawrie, William I. L.; Stehouwer, Lucas E. A.; Oosterhout, Stefan D.; Sammak, Amir; Friesen, Mark; Scappucci, Giordano; de Snoo, Sander L.; Rimbach-Russ, Maximilian; Borsoi, Francesco; Veldhorst, Menno
• 署名单位: Delft University of Technology; University of Wisconsin System; University of Wisconsin Madison
• 刊物名称: SCIENCE
• ISSN/ISSBN: 0036-10768
• DOI: 10.1126/science.ado5915
• 发表日期: 2024-07-26
• 页码: 447-452
• 关键词: qubit; germanium; FIDELITY

摘要

Qubits that can be efficiently controlled are essential for the development of scalable quantum hardware. Although resonant control is used to execute high-fidelity quantum gates, the scalability is challenged by the integration of high-frequency oscillating signals, qubit cross-talk, and heating. Here, we show that by engineering the hopping of spins between quantum dots with a site-dependent spin quantization axis, quantum control can be established with discrete signals. We demonstrate hopping-based quantum logic and obtain single-qubit gate fidelities of 99.97%, coherent shuttling fidelities of 99.992% per hop, and a two-qubit gate fidelity of 99.3%, corresponding to error rates that have been predicted to allow for quantum error correction. We also show that hopping spins constitute a tuning method by statistically mapping the coherence of a 10-quantum dot system. Our results show that dense quantum dot arrays with sparse occupation could be developed for efficient and high-connectivity qubit registers.