Orbital Selective Directional Conductor in the Two Orbital Hubbard Model

TL;DR

This paper reveals a novel antiferromagnetic orbital selective state in a two orbital Hubbard model, where one direction becomes insulating and the other metallic, influenced by temperature and electron interactions.

Contribution

It introduces a new orbital selective state with effective dimensional reduction in a two orbital Hubbard model, analyzed using a novel many-body technique including thermal effects.

Findings

Discovery of an antiferromagnetic orbital selective state at intermediate U

Identification of a narrow nematicity temperature window above Ne9el temperature

Finite-size scaling suggests nematicity persists in the bulk limit

Abstract

Employing a recently developed many-body technique that allows for the incorporation of thermal effects, the rich phase diagram of a two dimensional two orbital (degenerate $d_{xz}$ and $d_{yz}$) Hubbard model is presented varying temperature and the repulsion $U$. Our main result is the finding at intermediate $U$ of a novel antiferromagnetic orbital selective state where an effective dimensional reduction renders one direction insulating and the other metallic. Possible realizations of this state are discussed. In addition we also study nematicity above the N\'eel temperature. After a careful finite-size scaling analysis the nematicity temperature window appears to survive in the bulk limit although it is very narrow.