Metal to insulator transition at the surface of $V_2O_3$ thin films: an in-situ view

TL;DR

This study demonstrates that high-quality $V_2O_3$ thin films can be prepared and maintained in-situ, enabling detailed surface-sensitive investigations of the metal-insulator transition using advanced spectroscopic techniques.

Contribution

It introduces a method to produce and preserve clean $V_2O_3$ surfaces in thin films, facilitating surface studies of the MIT in strongly correlated materials.

Findings

Thin films replicate bulk $V_2O_3$ properties

In-situ transfer preserves surface quality

Enables ARPES studies of MIT

Abstract

$V_2O_3$ has long been studied as a prototypical strongly correlated material. The difficulty in obtaining clean, well ordered surfaces, however, hindered the use of surface sensitive techniques to study its electronic structure. Here we show by mean of X-ray diffraction and electrical transport that thin films prepared by pulsed laser deposition can reproduce the functionality of bulk $V_2O_3$. The same films, when transferred in-situ, show an excellent surface quality as indicated by scanning tunnelling microscopy and low energy electron diffraction, representing a viable approach to study the metal-insulator transition (MIT) in $V_2O_3$ by means of angle-resolved photoemission spectroscopy. Combined, these two aspects pave the way for the use of $V_2O_3$ thin films in device-oriented heterostructures.