Superconductivity from repulsion: Ginzburg-Landau phenomenology of cuprates

TL;DR

This paper presents a Ginzburg-Landau phenomenological model for cuprate superconductors based on eta_K-pairing, where superconductivity arises from repulsive Coulomb interactions, linking charge and orbital current order parameters to the phase diagram.

Contribution

It introduces a novel Ginzburg-Landau framework for eta_K-pairing in cuprates, connecting repulsive interactions to superconductivity and orbital order.

Findings

Phase diagram features explained by eta_K-pairing

Charge and orbital current orders linked to superconductivity

Reveals how repulsion can induce pairing in cuprates

Abstract

We develop Ginzburg-Landau approach to the problem of superconducting pairing with large momentum under screened Coulomb repulsion (eta_K-pairing). Two-component order parameter arising in this scheme can be associated with charge and orbital current degrees of freedom of the relative motion of eta_K-pair corresponding to superconducting and orbital antiferromagnetic ordered states, respectively. All basic features of the phase diagram of cuprate superconductors result directly from the eta_K-pairing concept.