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arXiv · 1807.09166

Thermopower-based hot electron thermometry of helium surface states at 1.6 K

Ethan I. Kleinbaum·Stephen A. Lyon
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Abstract

We have developed a method to probe the temperature of surface state electrons (SSE) above a superfluid Helium-4 surface using the Seebeck effect. In contrast to previously used SSE thermometry, this technique does not require detailed knowledge of the non-linear mobility. We demonstrate the use of this method by measuring energy relaxation of SSE at 1.6 K in a microchannel device with $0.6\:\mu\mbox{m}$ deep helium. In this regime, both vapor atom scattering and 2-ripplon scattering contribute to energy relaxation to which we compare our measurements. We conclude that this technique provides a reliable measure of electron temperature while requiring a less detailed understanding of the electron interactions with the environment than previously utilized thermometry techniques.

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Ethan I. Kleinbaum, Stephen A. Lyon. 2018-07-24. Thermopower-based hot electron thermometry of helium surface states at 1.6 K. https://doi.org/10.1103/physrevlett.121.236801

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