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arXiv · 1107.2296

The low temperature elastic anomalies in solid helium

Eric Varoquaux
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Abstract

The elastic properties of hcp $^4$He samples have been shown to display various anomalies. The elastic shear modulus stiffens and the moment of rotational inertia drops when the temperature is lowered below $\sim$ 0.2 K. The relation between these two quantities is studied within the framework of classical deformable-body mechanics. A model based on the formation by plastic flow of extremely soft two-dimensional layers of dislocations is studied analytically and numerically. This model accounts quantitatively for a number of experiments. Other situations, in which it may seem less relevant, are discussed.

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Eric Varoquaux. 2011-07-12. The low temperature elastic anomalies in solid helium. https://doi.org/10.1103/physrevb.86.064524

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