Antiferromagnetically Driven Electronic Correlation in Iron Pnictides and Cuprates

TL;DR

This paper explores how antiferromagnetic correlations influence electronic properties in iron pnictides and cuprates, using functional renormalization group methods to unify their behaviors and compare different model systems.

Contribution

It demonstrates that antiferromagnetic correlations are central to multiple ordering phenomena in these materials and shows how a double layer Hubbard model bridges cuprate and pnictide physics.

Findings

Antiferromagnetic correlations drive superconductivity, Fermi surface distortion, and orbital current order.

The double layer Hubbard model interpolates between cuprate and pnictide behaviors.

Renormalization group analysis of ladder models supports the unified framework.

Abstract

The iron pnictides and the cuprates represent two families of materials, where strong antiferromagnetic correlation drives three other distinct ordering tendencies: (1) superconducting pairing, (2) Fermi surface distortion, and (3) orbital current order. We propose that (1)-(3) and the antiferromagnetic correlation are the hallmarks of a class of strongly correlated materials to which the cuprates and pnictides belong. In this paper we present the results of the functional renormalization group studies to support the above claim. In addition, we show that as a function of the interlayer hopping parameter, the double layer Hubbard model nicely interpolates between the cuprate and the iron pnictide physics. Finally, as a check, we will present the renormalization group study of a ladder version of the iron pnictide, and compare the results to those of the two-dimensional model.