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

Area of Science:

• Condensed Matter Physics
• Quantum Fluids

Background:

• Solid helium-4 exhibits unique quantum phenomena, including quasi-one-dimensional superfluidity along dislocation cores.
• This superfluidity presents anomalous behaviors, such as pressure-dependent flow suppression and an unusual temperature dependence, contradicting existing theories like the Luttinger liquid paradigm.

Purpose of the Study:

• To investigate the underlying mechanisms responsible for the extraordinary features of the superflow-through-solid effect in solid helium-4.
• To explain the observed pressure suppression and temperature dependence of the superfluid flow rate.

Main Methods:

• The study employed ab initio and model simulations.
• Simulations focused on analyzing the impact of thermal fluctuations of dislocation shapes on the superfluid core.

Main Results:

• A strong correlation was found between thermal fluctuations of edge dislocations and asymmetric stress fields acting on the superfluid core.
• These stress fields were identified as the cause of the exponentially strong flow suppression with increasing pressure.
• The critical flux was shown to be highly sensitive to rare, strong fluctuations, leading to the observed sharp temperature dependence.

Conclusions:

• The anomalous superflow-through-solid effect in solid helium-4 is explained by thermal fluctuations of superclimbing edge dislocations.
• This provides a new understanding of critical flux behavior in quantum systems and challenges the standard Luttinger liquid model.