Supertransport by Superclimbing Dislocations in $^4$He: When All Dimensions Matter

TL;DR

This paper investigates the peculiar superflow in solid Helium-4 caused by superclimbing dislocations, revealing how thermal fluctuations and stress fields influence the flow's pressure and temperature dependence, challenging existing paradigms.

Contribution

It introduces a model linking dislocation shape fluctuations to superfluid flow suppression, providing new insights into supertransport in solid Helium-4.

Findings

Flow is exponentially suppressed by pressure increases.

Flow rate shows unusual temperature dependence.

Thermal fluctuations induce stress fields affecting superfluidity.

Abstract

The unique superflow-through-solid effect observed in solid Helium-4 and attributed to the quasi-one-dimensional superfluidity along the dislocation cores exhibits two extraordinary features: (i) an exponentially strong suppression of the flow by a moderate increase in pressure, and (ii) an unusual temperature dependence of the flow rate with no analogy to any known system and in contradiction with the standard Luttinger liquid paradigm. Based on ab initio and model simulations, we argue that the two features are closely related: Thermal fluctuations of the shape of a superclimbing edge dislocation induce large, correlated, and asymmetric stress fields acting on the superfluid core. The critical flux is most sensitive to strong rare fluctuations and hereby acquires a sharp temperature dependence observed in experiments.