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arXiv · 1002.2608

Frequency Dependence and Dissipation in the Dynamics of Solid Helium

Oleksandr Syshchenko James Day John Beamish
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Abstract

Torsional oscillator experiments on solid 4He show frequency changes which suggest mass decoupling, but the onset is broad and is accompanied by a dissipation peak. We have measured the elastic shear modulus over a broad frequency range, from 0.5 Hz to 8 kHz, and observe similar behavior - stiffening and a dissipation peak. These features are associated with a dynamical crossover in a thermally activated relaxation process in a disordered system rather than a true phase transition. If there is a transition in the DC response, e.g. to a supersolid state, it must occur below 55 mK.

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Oleksandr Syshchenko James Day John Beamish. 2010-04-13. Frequency Dependence and Dissipation in the Dynamics of Solid Helium. https://arxiv.org/abs/1002.2608

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