基于可编程SNS型约瑟夫森结阵的驱动系统研究

Research of driven system based on programmable SNS Josephson junction array

文章基于可编程SNS型约瑟夫森结阵,研究了一种交流量子电压驱动方法。该方法根据结阵的I-V特性,通过控制各段结阵的偏置状态及组合方式,实现交流量子电压的合成。采用电压源驱动方式,将节点电流分析法应用在偏置电路参数计算中,设计了偏置模块,搭建了交流约瑟夫森量子电压驱动系统。实验结果表明,该系统偏置电流的建立时间为1.27μs,稳定性优于6 n A/min,输出电流分辨率可达0.01 m A,可以合成频率为50 Hz、每周期40个采样点、有效值为1 V的交流约瑟夫森量子电压信号。

ased on the programmable SNS Josephson junction array,this paper studies a driven method of AC quantum voltage.According to the I-V characteristics of Junction array,this method realizes the synthesis of the AC quantum voltage by controlling the bias status and combination mode of each segment.The node current analysis method is applied to calculate the bias circuit parameters through using the voltage driven method,as a result,the bias module is designed,and the AC Josephson quantum voltage driven system is built.The experimental results show that the settling time of bias current is 1.27μs,the stability is better than 6 nA/min,and the output current resolution is 0.01 mA.This method has synthesized an AC quantum voltage with 50 Hz,40 sampling points per cycle,1 V RMS.