Is Li$_2$Pd$_3$B a self-doped hole superconductor ?

TL;DR

This paper suggests that Li$_2$Pd$_3$B is a self-doped correlated metal with a potential single-band t-J model describing its superconductivity, driven by Pd 4d-electrons and strong electronic correlations.

Contribution

It introduces a new perspective that Li$_2$Pd$_3$B is a self-doped metal and proposes a minimal 3D single-band t-J model for its superconductivity.

Findings

Li$_2$Pd$_3$B' is a self-doped correlated metal.

The material's electronic properties are dominated by Pd 4d-electrons.

A 3D single-band t-J model is proposed as the minimal model.

Abstract

We propose that the electrons responsible for superconductivity in Li2Pd3B come from the palladium 4d-electrons. So, its electronic properties are likely to be dominated by strong electronic correlations. The basic unit in this material are Pd$_6$B octahedra which share vertices to form a 3-dimensional network. Due to the highly distorted nature of the Pd$_6$B octahedron, one far stretched Pd atom per octahedra becomes almost inactive for electronic conduction. Thus, the material escapes the fate of becoming a half- filled insulating Mott antiferromagnet by hiding extra charges at these inactive Pd sites and becomes a self-doped correlated metal. We propose a 3-dimensional single band t-J model which could be the correct minimal model for this material.