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arXiv · 1007.1999

The glassy response of double torsion oscillators in solid Helium-4

Matthias J. Graf·Jung-Jung Su·Hari P. Dahal·I. Grigorenko·Zohar Nussinov
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Abstract

Single and double torsion oscillators have been used successfully to measure the anomalous change in resonant frequency and accompanying dissipation in solid He-4. We present a glass description of the mechanical anomalies found in torsion oscillator measurements. Our results show that it is not necessary to invoke a supersolid interpretation to explain these mechanical anomalies. Previously, we demonstrated that the back-action of a glassy subsystem present in solid He-4 can account for frequency change and dissipation peak in many single torsion oscillator experiments. Here, we show that the same glassy back-action can explain the experimental results of the composite torsion oscillator developed by the Rutgers group, which measures the response of solid He-4 at the in-phase mode f1=496 Hz and out-of-phase mode f2=1173 Hz.

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Matthias J. Graf, Jung-Jung Su, Hari P. Dahal, I. Grigorenko, Zohar Nussinov. 2010-12-01. The glassy response of double torsion oscillators in solid Helium-4. https://doi.org/10.1007/s10909-010-0320-2

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