Low Temperature Characteristics of the Metal–Superconductor NIS Tunneling Thermometer

Springer Science and Business Media LLC - Tập 207 - Trang 220-225 - 2022
Bayan Karimi1,2, Yu-Cheng Chang1, Jukka P. Pekola1
1Pico Group, QTF Centre of Excellence, Department of Applied Physics, Aalto University School of Science, Aalto, Finland
2QTF Centre of Excellence, Department of Physics, Faculty of Science, University of Helsinki, Helsinki, Finland

Tóm tắt

We discuss the temperature dependence of a common low temperature local thermometer, a tunnel junction between a superconductor and a normal metal (NIS junction). Towards the lowest temperatures its characteristics tend to saturate, which is usually attributed to selfheating effects. In this technical note, we reanalyze this saturation and show that the temperature independent subgap current of the junction alone explains in some cases the low temperature behavior quantitatively.

Tài liệu tham khảo

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