Hidden vortex lattices in a thermally paired superfluid

TL;DR

This paper investigates how a two-component superfluid transitions into a paired phase at finite temperature, revealing a shift from ordered vortex lattices to a disordered vortex tangle with hidden symmetry breaking.

Contribution

It introduces a hydrodynamic model capturing the transition and identifies the emergence of hidden vortex lattices and disordered vortex tangles during the phase change.

Findings

Transition causes vortex lattice symmetry change

Vortex state becomes highly disordered with reconnections

Hidden translational symmetry breaking observed

Abstract

We study the evolution of rotational response of a hydrodynamic model of a two-component superfluid with a non-dissipative drag interaction, as the system undergoes a transition into a paired phase at finite temperature. The transition manifests itself in a change of (i) vortex lattice symmetry, and (ii) nature of vortex state. Instead of a vortex lattice, the system forms a highly disordered tangle which constantly undergoes merger and reconnecting processes involving different types of vortices, with a "hidden" breakdown of translational symmetry.