Pitfalls and solutions for perovskite transparent conductors

TL;DR

This paper investigates the limitations of perovskite transparent conductors, revealing that reducing plasma frequency via electronic correlations increases optical absorption, and proposes alternative doping strategies for better performance.

Contribution

It provides ab-initio calculations showing the drawbacks of current strategies and suggests new approaches using hole doping and band engineering for improved transparent conductors.

Findings

Reducing plasma frequency increases optical absorption.

Electronic correlations cause enhanced scattering.

Hole doping and band separation improve transparency.

Abstract

Transparent conductors-nearly an oxymoron-are in pressing demand, as ultra-thin-film technologies become ubiquitous commodities. As current solutions rely on non-abundant elements, perovskites such as SrVO3 and SrNbO3 have been suggested as next generation transparent conductors. Our ab-initio calculations and analytical insights show, however, that reducing the plasma frequency below the visible spectrum by strong electronic correlations-a recently proposed strategy-unavoidably comes at a price: an enhanced scattering and thus a substantial optical absorption above the plasma edge. As a way out of this dilemma we identify several perovskite transparent conductors, relying on hole doping, somewhat larger bandwidths and separations to other bands.