约瑟夫森结参数对Shapiro台阶的影响研究  

Influence of Josephson Junction Parameters on Shapiro Steps

作　　者：刘飞连[1] 周铁戈[1] 王定城[1] 李娜[1] 赵新杰[1] 方兰[1] 阎少林[1] 

机构地区：[1]南开大学电子系,天津300071

出　　处：《电子学报》2009年第5期957-960,共4页Acta Electronica Sinica

基　　金：国家863高技术研究发展计划(No.2006AA03Z213);国家大学生创新性实验计划项目(No.NK0725);南开大学百项工程项目(No.BX6-230)

摘　　要：采用PSpice电路仿真的方法,研究了结电容C较小的情况下,电阻电容并联约瑟夫森结模型的参数(临界电流Ic和正常态电阻Rn)对Shapiro台阶高度的影响.发现在射频电流较大的情况下减小Rn可以提高台阶的高度,而在射频电流较小的情况下增加Rn可以提高台阶的高度.保持Rn不变,取不同Ic绘制的台阶高度-射频电流幅度曲线表明,临界电流越大,曲线所对应的台阶高度也越大.研究结果对利用约瑟夫森结作为电压标准和THz信号检测具有指导意义.The simulating model of Josephson junctions in PSpice is constructed and used in the investigation of Shapiro steps. In the condition of little capacitance, we have researched the influence of resistively and capacitively shunted Josephson junction＇ s parameters,including critical current and normal resistance,on Shapiro steps.We found that it can improve the steps by both to reduce the normal resistance under a larger if-current circumstance and to increase the normal resistance in the condition of a smaller if-current. We also found that the larger the junction critical current, the higher the Shapiro steps, when the junction resistance keeps constant. The results are of important referential value for the voltage standard and THz signal detection by Josephson junctions.

关 键 词：约瑟夫森结 Shapiro台阶 电压标准 THz信号检测 

分 类 号：TN12[电子电信—物理电子学]