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arXiv · 2503.09879

Quantum Computer Controlled by Superconducting Digital Electronics at Millikelvin Temperature

Caleb Jordan·Jacob Bernhardt·Joseph Rahamim·Alex Kirichenko·Karthik Bharadwaj·Louis Fry-Bouriaux·Aaron Somoroff·Katie Porsch·Kan-Ting Tsai·Jason Walter·Adam Weis·Meng-Ju Yu·Mario Renzullo·Jerome Javelle·Chris Checkley·Oleg Mukhanov·Daniel Yohannes·Igor Vernik·Shu-Jen Han
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Abstract

Current superconducting quantum computing platforms face significant scaling challenges, as individual signal lines are required for control of each qubit. This wiring overhead is a result of the low level of integration between control electronics at room temperature and qubits operating at millikelvin temperatures, which raise serious doubts among technologists about whether utility-scale quantum computers can be built. A promising alternative is to utilize cryogenic, superconducting digital control electronics that coexist with qubits. Here, we report the first multi-qubit system integrating this technology. The system utilizes digital demultiplexing, breaking the linear scaling of control lines to number of qubits. We also demonstrate single-qubit fidelities above 99%, and up to 99.9%. This work is a critical step forward in realizing highly scalable chip-based quantum computers.

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Caleb Jordan, Jacob Bernhardt, Joseph Rahamim, Alex Kirichenko, Karthik Bharadwaj, Louis Fry-Bouriaux, Aaron Somoroff, Katie Porsch, Kan-Ting Tsai, Jason Walter, Adam Weis, Meng-Ju Yu, Mario Renzullo, Jerome Javelle, Chris Checkley, Oleg Mukhanov, Daniel Yohannes, Igor Vernik, Shu-Jen Han. 2025-03-12. Quantum Computer Controlled by Superconducting Digital Electronics at Millikelvin Temperature. https://doi.org/10.1038/s41928-026-01576-6

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