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arXiv · 2211.06174

Effect of Magnetic Scattering on Superfluid Transition of 3He in Nematic Aerogel

V. V. Dmitriev·M. S. Kutuzov·A. A. Soldatov·A. N. Yudin
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Abstract

We present results of high magnetic field experiments in pure $^3$He (in the absence of $^4$He coverage) in nematic aerogel. In this case the aerogel strands are covered with few atomic layers of solid paramagnetic $^3$He, which enables the spin-exchange mechanism for $^3$He quasiparticles scattering. Our earlier NMR experiments showed that in low fields, instead of the polar phase, the A phase is expected to emerge in nematic aerogel. We use a vibrating wire resonator with the sample of aerogel attached to it and measure temperature dependencies of resonance properties of the resonator at different magnetic fields. A superfluid transition temperature of $^3$He in aerogel, obtained from the experiments, increases nonlinearly in applied magnetic field. And this increase is suppressed compared with that for bulk A$_1$ phase, which we attribute to an influence of the magnetic scattering channel, previously considered theoretically for the case of $^3$He confined in isotropic silica aerogel. However, we observe the essential quantitative mismatch with theoretical expectations.

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V. V. Dmitriev, M. S. Kutuzov, A. A. Soldatov, A. N. Yudin. 2022-11-11. Effect of Magnetic Scattering on Superfluid Transition of 3He in Nematic Aerogel. https://doi.org/10.1103/physrevb.107.024507

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