Strength of Correlations in electron and hole doped cuprates

TL;DR

This paper investigates the fundamental differences between electron and hole doped cuprates, revealing that electron doping leads to Slater insulators driven by magnetic order, unlike the Mott insulator behavior in hole doping.

Contribution

The study uses a new first principles method to explain why electron and hole doped cuprates exhibit different insulating behaviors and magnetic properties.

Findings

Electron doped cuprates are Slater insulators with magnetic order.

Hole doped cuprates are Mott insulators driven by electronic correlations.

Distinct physical mechanisms underlie the insulating states in electron vs. hole doping.

Abstract

High temperature superconductivity was achieved by introducing holes in a parent compound consisting of copper oxide layers separated by spacer layers. It is possible to dope some of the parent compounds with electrons, and their physical properties are bearing some similarities but also significant differences from the hole doped counterparts. Here, we use a recently developed first principles method, to study the electron doped cuprates and elucidate the deep physical reasons why their behavior is so different than the hole doped materials. We find that electron doped compounds are Slater insulators, e.g. a material where the insulating behavior is the result of the presence of magnetic long range order. This is in sharp contrast with the hole doped materials, where the parent compound is a Mott charge transfer insulator, namely a material which is insulating due to the strong electronic correlations but not due to the magnetic order.