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arXiv · 2505.00297

A Low-Noise and High-Stability DC Source for Superconducting Quantum Circuits

Daxiong Sun·Jiawei Zhang·Peisheng Huang·Yubin Zhang·Zechen Guo·Tingjin Chen·Rui Wang·Xuandong Sun·Jiajian Zhang·Wenhui Huang·Jiawei Qiu·Ji Chu·Ziyu Tao·Weijie Guo·Xiayu Linpeng·Ji Jiang·Jingjing Niu·Youpeng Zhong·Dapeng Yu
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Abstract

With the rapid scaling of superconducting quantum processors, electronic control systems relying on commercial off-the-shelf instruments face critical bottlenecks in signal density, power consumption, and crosstalk mitigation. Here we present a custom dual-channel direct current (DC) source module (QPower) dedicated for large-scale superconducting quantum processors. The module delivers a voltage range of $\pm$7 V with 200 mA maximum current per channel, while achieving the following key performance benchmarks: noise spectral density of 20 nV/$\sqrt{\mathrm{Hz}}$ at 10 kHz, output ripple $<$500 $\mu$V$_{\mathrm{pp}}$ within 20 MHz bandwidth, and long-term voltage drift $<$5 $\mu$V$_{\mathrm{pp}}$ over 12 hours. Integrated into the control electronics of a 66-qubit quantum processor, QPower enables qubit coherence times of $T_1 = 87.6~\mu\mathrm{s}$ and Ramsey $T_2 = 5.1~\mu\mathrm{s}$, with qubit resonance frequency drift constrained to $\pm$40 kHz during 12-hour operation. This modular design is compact in size and efficient in energy consumption, providing a scalable DC source solution for intermediate-scale quantum processors with stringent noise and stability requirements, with potential extensions to other quantum hardware platforms and precision measurement.

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Daxiong Sun, Jiawei Zhang, Peisheng Huang, Yubin Zhang, Zechen Guo, Tingjin Chen, Rui Wang, Xuandong Sun, Jiajian Zhang, Wenhui Huang, Jiawei Qiu, Ji Chu, Ziyu Tao, Weijie Guo, Xiayu Linpeng, Ji Jiang, Jingjing Niu, Youpeng Zhong, Dapeng Yu. 2025-05-01. A Low-Noise and High-Stability DC Source for Superconducting Quantum Circuits. https://arxiv.org/abs/2505.00297

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