Superconductivity From Repulsive Electronic Correlations on Alternant Cuprate and Iron-based Lattices

TL;DR

This paper demonstrates that high-temperature superconductivity can emerge from purely repulsive electronic interactions in alternant cuprate and iron-based lattices, where electron pairing avoids repulsion and resides in attractive regions.

Contribution

It introduces a mechanism where repulsive correlations induce superconductivity through lattice structure and pairing symmetry, a novel approach in high-Tc theory.

Findings

Superconducting states can form with electrons avoiding repulsive interactions.

Alternant lattice structure stabilizes high-temperature superconductivity.

Various pairing symmetries like dx2 -y2 and s-wave are supported.

Abstract

A key question in the theory of high-temperature superconductivity is whether Off-diagonal Long-Range Order (ODLRO) can be induced wholly or in large part by repulsive electronic correlations. Electron pairs on Cuprate and the iron-based pnictide and chalcogenide alternant lattices may interact with a strong short-range Coulomb repulsion and much weaker longer range attractive tail. Here we show that such interacting electrons can cooperate to produce a superconducting state in which time-reversed electron pairs effectively avoid the repulsive part but reside predominantly in the attractive region of the potential. The alternant lattice structure is a key feature of such a stabilization mechanism leading to the occurrence of high temperature superconductivity with dx2 -y2 or sign alternating s-wave or s plus/minus condensate symmetries.