High Temperature Superconductor-Normal Metal-Superconductor Josephson Junctions with High Characteristic Voltages
High Temperature Superconductor-Normal Metal-Superconductor Josephson Junctions with High Characteristic Voltages
复制标题
具有高特征电压的高温超导-普通金属-超导约瑟夫森结
DOI：
10.1063/1.110622
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
L. Vale
中科院分区：
文献类型：
--
作者：
P. Rosenthal;E. Grossman;R. Ono;L. Vale
我们使用YBa 2Cu 3 O 7 −x（YBCO）和贵金属制造了阶跃边缘超导体-正常金属-超导体微桥，其临界电流-正常电阻（IcRN）乘积高达10 mV，正常电阻高达38 Ω。我们的制造工艺实现了高价值的IcRN产品，通过利用外延YBCO薄膜的各向异性的属性，允许正常金属和超导体之间的接触，通过支持最大的约瑟夫森耦合的晶轴。这导致结的正常电阻急剧增加，而不降低其临界电流。我们讨论了超导体-正常金属边界电阻对结电性能的作用。我们将亚毫米波射频电流准光学地耦合到集成在贵金属平面对数周期天线的馈电处的结中，并利用来自远红外激光器的760 GHz光束在电流-电压特性中诱导了多达7个Shapiro步骤。
We have fabricated step edge superconductor‐normal metal‐superconductor microbridges using YBa2Cu3O7−x(YBCO) and noble metals with critical current‐normal resistance (IcRN) products as high as 10 mV and normal resistances up to 38 Ω. Our fabrication process achieves high values of the IcRN product by exploiting the anisotropy in the properties of epitaxial YBCO films, allowing contact only between normal metal and superconductor through the crystalline axes which support the largest Josephson coupling. This results in a dramatic increase in the normal resistance of a junction without decreasing its critical current. We discuss the role of the superconductor‐normal metal boundary resistance on the junction electrical properties. We have coupled submillimeter wave rf currents quasioptically into junctions integrated at the feeds of noble metal planar log periodic antennas and have induced up to 7 Shapiro steps in the current‐voltage characteristics with a 760 GHz beam from a far infrared laser.