Anisotropy-induced Vortex Core Transitions in Superfluid 3He in Aerogel

TL;DR

This study uses numerical solutions of Ginzburg-Landau equations to explore how uniaxial deformation of aerogel influences vortex core structures in superfluid 3He, revealing deformation-dependent vortex core transitions.

Contribution

It demonstrates how uniaxial compression and stretching of aerogel affect vortex core transitions in superfluid 3He, providing new insights into the interplay between aerogel deformation and superfluid vortex structures.

Findings

Vortex core transition (VCT) appears in B-like phase under compression.

No strange vortex core expected in A-like phase with compression.

Stretching aerogel alters VCT behavior, inducing transitions in A-like phase.

Abstract

Core structures of a single vortex in A-like and B-like phases of superfluid 3He in uniaxially compressed and stretched aerogels are studied by numerically solving Ginzburg-Landau equations derived microscopically. It is found that, although the A-like phase with axial pairing is extended by any uniaxial deformation, the vortex core states in the two phases depend highly on the type of deformation in aerogel: In a compressed aerogel, the first order vortex core transition (VCT) previously seen in the bulk B phase appears at any pressure in B-like phase, while no strange vortex core is expected in A-like phase. By contrast, in a stretched aerogel, the VCT in B-like phase is lost, while another VCT is expected to occur between a nonunitary core and the polar one in A-like phase. An experimental search for these results is hoped to understand correlation between superfluid $^3$He and aerogel structures.