Vortex matter in $U(1)\times U(1)\times {\mathbb{Z}}_2$ phase-separated superconducting condensates

Abstract

We study the properties of vortex solutions and magnetic response of two-component $U(1)\times U(1)\times {\mathbb{Z}}_2$ superconductors, with phase separation driven by intercomponent density-density interaction. Such a theory can be viewed arising from the breakdown of $SU(2)$ symmetry by a biquadratic interaction between the components of the field. Depending on the symmetry-breaking term, there are two ground-state phases: one where both components of the doublet are equal (the miscible phase) and one where only one component assumes a non zero vacuum expectation value (the immiscible state). In the latter phase, the spectrum of topological excitations contains both domain walls and vortices. We show the existence of another kind of excitation that has properties of both topological excitations at the same time. They combine vorticity together with a circular domain wall, interpolating between inequivalent broken states, that shows up as a ring of localized magnetic flux. Asymptotically, this resembles a vortex carrying multiple flux quanta, but because the magnetic field is localized at a given distance from the center this looks like a pipe. The isolated multiquanta pipelike vortices can be either stable or metastable, even if the system is not type-1. We also discuss the response of such a system to an externally applied magnetic field.

6 pages, 8 figures

References in corpus (4)

• Charge $4e$ superconductivity from pair density wave order in certain high temperature superconductors
• Dislocations and vortices in pair density wave superconductors
• Twisted Superconducting Semilocal Strings
• Stability Analysis of The Twisted Superconducting Semilocal Strings

Cited by in corpus (3)

• Order Fractionalization in a Kitaev-Kondo model
• Vortex chains due to nonpairwise interactions and field-induced phase transitions between states with different broken symmetry in superconductors with competing order parameters
• Vortices and magnetic bags in Abelian models with extended scalar sectors and some of their applications