Domain Wall Conductivity in Oxygen Deficient Multiferroic YMnO3 Single Crystals

TL;DR

This study investigates how oxygen vacancies influence the electrical conductance of domain walls in YMnO3 multiferroic crystals, revealing mechanisms and ways to modulate their conductivity for potential applications.

Contribution

It demonstrates that oxygen vacancy ordering enhances domain wall conductance and can be controlled via electric poling, introducing a new method for tuning multiferroic properties.

Findings

Domain walls show increased conductance after electric poling.

Conductance mechanisms include Schottky emission and Fowler-Nordheim tunnelling.

Oxygen vacancy ordering modulates domain wall conductivity.

Abstract

The transport properties of domain walls in oxygen deficient multiferroic YMnO3 single crystals have been probed using conductive atomic force microscopy and piezoresponse force microscopy. Domain walls exhibit significantly enhanced conductance after being poled in electric fields, possibly induced by oxygen vacancy ordering at domain walls. The electronic conduction can be understood by the Schottky emission and Fowler-Nordheim tunnelling mechanisms. Our results show that the domain wall conductance can be modulated through band structure engineering by manipulating ordered oxygen vacancies in the poling fields.