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arXiv · 2603.27231

Ultralow-power coherent qubit control using AQFP logic at millikelvin temperatures

Hiroto Mukai·Akiyoshi Tomonaga·Rui Wang·Yu Zhou·Taro Yamashita·Nobuyuki Yoshikawa·Jaw-Shen Tsai·Naoki Takeuchi
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Abstract

Qubit controllers are essential for scaling superconducting quantum processors, but implementing them at the 10 mK stage of a dilution refrigerator remains challenging due to stringent cooling constraints. Here we report an ultralow-power qubit controller using adiabatic quantum-flux-parametron (AQFP) logic, termed an AQFP-multiplexed qubit controller with virtual Z gates (AQFP QC-VZ). The AQFP QC-VZ generates multi-tone microwave pulses for qubit control with an ultralow power dissipation of 111 pW per qubit. By combining microwave and time-division multiplexing, the AQFP QC-VZ enables parallel application of X and virtual Z gates to multiple qubits using only a few control lines from room temperature. We demonstrate coherent single-qubit gates at the 10 mK stage using an AQFP mixer, a core component of the AQFP QC-VZ, without observable degradation in coherence.

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Hiroto Mukai, Akiyoshi Tomonaga, Rui Wang, Yu Zhou, Taro Yamashita, Nobuyuki Yoshikawa, Jaw-Shen Tsai, Naoki Takeuchi. 2026-03-28. Ultralow-power coherent qubit control using AQFP logic at millikelvin temperatures. https://arxiv.org/abs/2603.27231

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