Interplay of non-linear elasticity and dislocation-induced superfluidity in solid Helium-4

TL;DR

This paper explores how non-linear elasticity and dislocation-induced superfluidity interact in solid Helium-4, proposing mechanisms for impurity binding and superfluid response suppression, with implications for understanding its unique quantum properties.

Contribution

It introduces a novel scenario linking dislocation kinks to superfluid suppression and impurity binding, advancing the understanding of solid Helium-4's elastic and superfluid behaviors.

Findings

Helium-3 impurities remain bound at high temperatures due to long equilibration times.

Dislocation kinks suppress superfluidity along dislocation cores.

The proposed mechanisms explain the similarity between elastic and superfluid responses.

Abstract

The mechanism of the roughening induced partial depinning of gliding dislocations from Helium-3 impurities is proposed as an alternative to the standard "boiling off". We give a strong argument that Helium-3 remains bound to dislocations even at large temperatures due to very long equilibration times. A scenario leading to the similarity between elastic and superfluid responses of solid Helium-4 is also discussed. Its main ingredient is a strong suppression of the superfluidity along dislocation cores by dislocation kinks (D. Aleinikava, et. al., arXiv:0812.0983). These kinks, on one hand, determine the temperature and Helium-3 dependencies of the generalized shear modulus and, on the other hand, control the superfluid response. Several proposals for theoretical and experimental studies of solid Helium-4 are suggested.