Electronic structure of higher-order layered palladates: La$_{n+1}$Pd$_{n}$O$_{2n+1}$ $(n = 4-7)$

TL;DR

This study uses ab initio calculations to explore the electronic structure of higher-order layered palladates, revealing properties that make them promising candidates for unconventional superconductivity, similar to cuprates.

Contribution

First theoretical investigation of higher-order layered palladates' electronic structure, highlighting their potential as cuprate analogs for superconductivity.

Findings

Layered palladates have larger bandwidths and increased p-d hybridization.

Less interference from R-d bands at the Fermi level in palladates.

Properties make palladates promising for unconventional superconductivity.

Abstract

The square-planar layered nickelates R$_{n+1}$Ni$_n$O$_{2n+2}$ (R= Nd, $n=4-7$) have been recently shown to be superconducting without the need for chemical doping or pressure. Here, we examine the electronic structure of the analog higher-order square-planar palladates --that have not yet been synthesized-- via \textit{ab initio} calculations. These layered palladates exhibit larger bandwidths, an increased $p-d$ hybridization, and less interference from R-$d$ bands at the Fermi level. These characteristics make them closer cuprate analogs and promising candidates to pursue in the context of unconventional superconductivity.