Thin Flim Squids of High TC Materials

我们提出基于约瑟夫森结的非线性电压电流特性来制作和测试微波器件。特别是单孔和双孔微波SQUID（超导量子干涉探测器）器件和利用结的非线性特性的平面微波传感器。为了利用最新的蚀刻技术，这些结将被离子束铣削到100A的公差。本文只研究电接地在薄膜平面上的平面器件。将采用激光沉积YBCO薄膜。我们将推导出临界电流Ic和电阻R与结的制造参数之间的基本关系，以便估计结中的微波特性。除了计算微波场存在下结的直流电压-电流特性外，还将首次从理论上计算微波反射（S11）和透射（S21）系数。SQUID器件和微波平面器件的测量性能将根据结或弱环节的流态动力学和自由能进行建模。

We propose to fabricate and test microwave devices based upon the non-linear voltage current characteristics of Josephson junctions. In particular one and two-hole microwave SQUID (Supercon- ducting Quantum Interference Detectors) devices and planar microwave sensors utilizing the non-linear characteristics of the junction will be fabricated. The junctions will be ion beam milled to tolerances of 100A in order to take advantage of the latest advances in etching techniques. Only planar devices with the electrical ground in the plane of the film will be studied. Laser deposited YBCO films will be used. We will derive fundamental relationships between the critical current, Ic, and resistance, R, and the fabrication parameters of the junction in order to estimate microwave properties in the junctions. In addition to the calculation of D.C. voltage-current characteristics of a junction in the presence of a microwave field, microwave reflection (S11) and transmission (S21) coefficients will be theoretically calculated for the first time. Measured performance of SQUID devices and microwave planar devices will be modeled in terms of the fluxoid dynamics and free energy of the junction or weak links.