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arXiv · 0907.4965

The glassy response of solid He-4 to torsional oscillations

M. J. Graf·Z. Nussinov·A. V. Balatsky
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Abstract

We calculated the glassy response of solid He-4 to torsional oscillations assuming a phenomenological glass model. Making only a few assumptions about the distribution of glassy relaxation times in a small subsystem of otherwise rigid solid He-4, we can account for the magnitude of the observed period shift and concomitant dissipation peak in several torsion oscillator experiments. The implications of the glass model for solid He-4 are threefold: (1) The dynamics of solid He-4 is governed by glassy relaxation processes. (2) The distribution of relaxation times varies significantly between different torsion oscillator experiments. (3) The mechanical response of a torsion oscillator does not require a supersolid component to account for the observed anomaly at low temperatures, though we cannot rule out its existence.

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M. J. Graf, Z. Nussinov, A. V. Balatsky. 2009-07-28. The glassy response of solid He-4 to torsional oscillations. https://doi.org/10.1007/s10909-009-9958-z

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