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Andreev Reflections in Micrometer-Scale Normal Metal-Insulator-Superconductor Tunnel Junctions



Peter J. Lowell, Galen C. O'Neil, Jason M. Underwood, Joel N. Ullom


Understanding the subgap behavior of Normal-Insulator-Superconductor (NIS) tunnel junctions is important in order to be able to accurately model the thermal properties of the junctions. Hekking and Nazarov developed a theory in which the NIS sub gap current can be modeled by multiple Andreev reflections. In their theory, the current caused by Andreev reflections depends on the junction area and junction resistance area product. We have measured the Andreev current in Normal-Insulator-Superconductor (NIS) tunnel junctions for various junction sizes and junction resistance area products and found that Hekking and Nazarov's theory is in agreement with our data.
Journal of Low Temperature Physics


Andreev Reflection, Subgap Conductance, Superconducting Tunnel Junctions


Lowell, P. , O'Neil, G. , Underwood, J. and Ullom, J. (2011), Andreev Reflections in Micrometer-Scale Normal Metal-Insulator-Superconductor Tunnel Junctions, Journal of Low Temperature Physics, [online], (Accessed April 25, 2024)
Created November 24, 2011, Updated November 10, 2018