Real Space Coulomb Interaction: A Pairing Glue for FeAs Superconductors

TL;DR

This paper proposes a real space Coulomb interaction mechanism as a pairing glue in FeAs superconductors, explaining pseudogap formation and providing a criterion to predict its occurrence.

Contribution

It introduces a novel Coulomb-based pairing mechanism in real space for FeAs superconductors and a criterion to determine pseudogap presence.

Findings

Coulomb interaction can bind electrons in FeAs layers

The mechanism explains pseudogap phenomena in underdoped samples

A criterion predicts pseudogap occurrence in materials

Abstract

In this paper we present a real space pairing glue for the iron-based layered superconductors. It is shown that two static electrons embedded symmetrically into two adjacent Fe plaquettes of the superconductor can be bounded due to the Coulombic interaction. The pairing mechanism favors the existence of the pseudogap in the underdoped FeAs superconductors. A criterion is introduced to distinguish whether or not the pseudogap can open in a material.