A Practical Two-Stage SQUID Readout Circuit Improved With Proportional Feedback Schemes
A Practical Two-Stage SQUID Readout Circuit Improved With Proportional Feedback Schemes
复制标题
采用比例反馈方案改进的实用两级 SQUID 读出电路
DOI：
10.1109/tasc.2020.2970230
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发表时间：
2020-01
影响因子：
1.8
通讯作者：
Xie Xiaoming
中科院分区：
文献类型：
--
作者：
Wang Yongliang;Zhang Guofeng;Zhang Shulin;Dong Hui;Rong Liangliang;Wang Yong;Xie Xiaoming
多工作点非线性限制了具有低噪声性能的两级超导量子干涉仪（SQUID）读出电路的实际应用。为了解决这个问题，提出了一种简单的两级SQUID读出电路，该电路采用比例反馈方案对两个传统的直流SQUID进行改进，其中第一级SQUID电路的传输系数通过附加的正反馈电路得到提高，第二级SQUID电路的传输特性通过附加的负反馈电路得到线性化。基于匹配条件，两种比例反馈方案协同工作，实现了噪声抑制和工作点匹配。实验结果验证了其工作原理。所实现的整体传输特性仅具有一个工作点，并且根据放大器的电压摆幅简单地进行调整。第一级SQUID电路的传输系数提高到10（20 dB），两级SQUID读出电路的总磁通噪声降低到1 μΦ0/kHz以下，其中Φ0 = 2.07 ×10−15 Wb。我们的两级SQUID读出电路易于操作，适用于高性能实用SQUID系统。
Nonlinearity with multiple working points limits the practical applications of a two-stage superconducting quantum interference device (SQUID) readout circuit, which is promising for low-noise performance. To solve this problem, we proposed a simple two-stage SQUID readout circuit with two conventional dc SQUIDs improved with proportional feedback schemes, where transfer coefficient of the first-stage SQUID circuit is enhanced by additional positive feedback circuit; transfer characteristics of the second-stage SQUID circuit are linearized by an additional negative feedback circuit. Two proportional feedback schemes are cooperated together based on matching conditions to achieve both noise suppression and working point matching. Working principles were verified in experiment results. The overall transfer characteristics achieved have only one working point and are simply adjusted according to the voltage swing of an amplifier. Transfer coefficient of the first-stage SQUID circuit was raised up to 10 (20 dB), and the total flux noise of two-stage SQUID readout circuit was reduced below 1 μΦ0/√Hz, where Φ0 = 2.07 ×10−15 Wb. Our two-stage SQUID readout circuit is easy-to-operate and suited for high-performance practical SQUID systems.
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影响因子：
1.8
作者：
R. Cantor;L.P. Lee;A. Matlashov;V. Vinetskiy
通讯作者：
R. Cantor;L.P. Lee;A. Matlashov;V. Vinetskiy
影响因子：
3.6
作者：
DRUNG, D;KOCH, H
通讯作者：
KOCH, H
影响因子：
2.1
作者：
V. Foglietti;M. Giannini;G. Petrocco
通讯作者：
V. Foglietti;M. Giannini;G. Petrocco
影响因子：
3.6
作者：
M. Kiviranta
通讯作者：
M. Kiviranta
影响因子：
1.6
作者：
R. Forgacs;A. Warnick
通讯作者：
R. Forgacs;A. Warnick