Singular Vortex in Narrow Cylinders of Superfluid 3He-A Phase

TL;DR

This paper investigates the vortex structures in superfluid 3He-A confined in narrow cylinders using Ginzburg-Landau theory, identifying a transition from radial disgyration to Mermin-Ho textures under rotation, relevant for ongoing experiments.

Contribution

It provides a detailed numerical analysis of vortex textures in superfluid 3He-A in narrow cylinders, incorporating full orbital and spin degrees of freedom, and predicts a specific transition under rotation.

Findings

Radial disgyration texture identified as ground state at rest.

Transition from radial disgyration to Mermin-Ho texture at critical rotation speed.

Provides experimental predictions for vortex behavior in narrow cylinders.

Abstract

Motivated by the on-going rotating cryostat experiments in ISSP, Univ. of Tokyo, we explore the textures and vortices in superfluid 3He-A phase confined in narrow cylinders, whose radii are R=50mum and 115mum. The calculations are based on the Ginzburg-Landau (GL) framework, which fully takes into account the orbital (l-vector) and spin (d-vector) degrees of freedom for chiral p-wave pairing superfluid. The GL free energy functional is solved numerically by using best known GL parameters appropriate for the actual experimental situations at P=3.2MPa and H=21.6mT. We identify the ground state l-vector configuration as radial disgyration (RD) texture with the polar core both at rest and low rotations and associated d-vector textures for both narrow cylinder systems under high magnetic fields. The RD which has a singularity at center, changes into Mermin-Ho texture above the critical rotation speed which is determined precisely, providing an experimental check for own proposal.