Using vibrating wire in non-linear regime as a thermometer in superfluid $^3$He-B

V. V. Zavjalov

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arXiv · 2303.01189

Using vibrating wire in non-linear regime as a thermometer in superfluid $^3$He-B

V. V. Zavjalov

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Abstract

Vibrating wires are common temperature probes in $^3$He experiments. By measuring mechanical resonance of a wire driven by AC current in magnetic field one can directly obtain temperature-dependent viscous damping. This is easy to do in a linear regime where wire velocity is small enough and damping force is proportional to velocity. At lowest temperatures in superfluid $^3$He-B a strong non-linear damping appears and linear regime shrinks to a very small velocity range. Expanding measurements to the non-linear area can significantly improve sensitivity. In this note I describe some technical details useful for analyzing such temperature measurements.

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V. V. Zavjalov. 2023-03-02. Using vibrating wire in non-linear regime as a thermometer in superfluid $^3$He-B. https://arxiv.org/abs/2303.01189

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