Coexistence of magnetic and charge order in a two-component order parameter description of the layered superconductors

TL;DR

This paper introduces a two-component order parameter model for layered superconductors, revealing an inhomogeneous, topologically stable condensate with magnetic and charge order that exists without external magnetic fields.

Contribution

It presents a novel two-component order parameter framework that describes coexistence of magnetic and charge order in layered superconductors, including inhomogeneous and topologically stable states.

Findings

Inhomogeneous condensate with magnetic and charge degrees of freedom

Charge density exhibits hexadecapole moment

Time reversal symmetry is broken without detectable magnetic fields

Abstract

A two-component order parameter approach for the layered superconductor is shown to form a condensate with magnetic and charge degrees of freedom. This condensate is an inhomogeneous state, topologically stable, that exists without the presence of an applied magnetic field. We show that the charge density in the layers presents hexadecapole moment in its lowest order. Our approach is based on the first order equations that we show here to solve the variational equations for the special temperature defined by the crossing of the superconducting dome and the pseudogap transition line. Time reversal symmetry is broken and the weak local magnetic field produced by this inhomogeneous state falls below the threshold of experimental observation. We find that the charge distribution in the layers has an hexadecapole moment in its lowest order.