具有Washer型输入线圈的超导量子干涉放大器的制备与表征  

Fabrication and characterization of the superconducting quantum interference device amplifier with Washer type input coil

作　　者：陈钊[1] 何根芳 张青雅[1] 刘建设[1] 李铁夫[1] 陈炜[1] 

机构地区：[1]清华大学,信息科学与技术国家实验室,微纳电子学系,微电子学研究所,北京100084

出　　处：《物理学报》2015年第12期412-418,共7页Acta Physica Sinica

基　　金：国家重点基础研究发展计划(批准号:2011CBA00304);清华大学自主科研计划(批准号:20131089314)资助的课题~~

摘　　要：超导量子干涉仪(SQUID)放大器具有低输入阻抗、低噪声、低功耗等优点,目前被广泛用于微弱信号的检测领域.与其他工艺相比,Nb/Al-Al Ox/Nb结构的约瑟夫森结具有相对较高的转变温度(Tc)、高的磁通电压调制系数以及良好的热循环能力、较宽的临界电流范围,因此是制备SQUID放大器的很好选择.设计并制作了欠阻尼、过阻尼约瑟夫森结以及具有Washer型输入线圈的单SQUID放大器,通过在He3制冷机3 K温区下对器件电流-电压特性进行测量,得到良好的结I-V特性曲线、SQUID调制特性,初步实现利用SQUID进行放大作用,并计算了SQUID的电流分辨率.此项工作对于超导转变边沿传感器读出电路的实现具有重要的意义.Superconducting quantum interference device （SQUID） amplifier is best known for its low input impedance, low noise and low power consumption. Nowadays it is widely used for detecting the weak signals. Compared with other methods, the Nb/Al-AlOx/Nb structure Josephson junction based SQUID has the advantages of high transition temperature, high voltage flux modulation index and good heat recycle ability, wide critical voltage range, so it is a very good option for making SQUID amplifier. In this work, we fabricate the overdamped Josephson junction and washer dc SQUID, and test the I-V characteristics at He^3 K stage temperature and calculate the current resolution of SQUID. The result of SQUID modulation property is good. The magnification becomes larger after increasing the input line number of loops, and the system noise becomes smaller after the join of the LC filter. This work is very important for designing and manufacturing transition edge sensor readout circuits.

关 键 词：超导量子干涉放大器 超导量子干涉仪 约瑟夫森结 超导转变边沿传感器 

分 类 号：TN722[电子电信—电路与系统]