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arXiv · 0810.2525

Viscoelastic Behavior of Solid $^4$He

Chi-Deuk Yoo·Alan T. Dorsey
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Abstract

Over the last five years several experimental groups have reported anomalies in the temperature dependence of the period and amplitude of a torsional oscillator containing solid $^4$He. We model these experiments by assuming that $^4$He is a viscoelastic solid--a solid with frequency dependent internal friction. We find that while our model can provide a quantitative account of the dissipation observed in the torsional oscillator experiments, it only accounts for about 10% of the observed period shift, leaving open the possibility that the remaining period shift is due to the onset of superfluidity in the sample.

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Chi-Deuk Yoo, Alan T. Dorsey. 2008-10-14. Viscoelastic Behavior of Solid $^4$He. https://doi.org/10.1103/physrevb.79.100504

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