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arXiv · 2107.07858

Design of a system for controlling a levitating sphere in superfluid $^3$He at extremely low temperatures

M. Arrayás·José L. Trueba·Carlos Uriarte·Dmitry E. Zmeev
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Abstract

We present a new mechanical probe to study the properties of superfluid $^3$He at microkelvin temperatures down to 100$μ$K. The setup consists of a set of coils for levitating a superconducting sphere and controlling its motion in a wide variety of regimes. In particular, the realisation of motion of a levitating body at a uniform velocity presents both an experimental challenge and a promising direction into the study of the edge states in topological superfluid $^3$He-B. We include the theoretical study of the device stability and simulations to illustrate the capabilities of the control system.

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M. Arrayás, José L. Trueba, Carlos Uriarte, Dmitry E. Zmeev. 2021-07-16. Design of a system for controlling a levitating sphere in superfluid $^3$He at extremely low temperatures. https://doi.org/10.1038/s41598-021-99316-7

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