Manipulating the anisotropic phase separation in strained VO2 epitaxial films by nanoscale ion-implantation

TL;DR

This study demonstrates how nanoscale ion-implantation can control and visualize anisotropic phase separation in strained VO2 films, revealing new insights into nanoscale electronic phase behavior in correlated oxides.

Contribution

It introduces a method to manipulate and directly observe anisotropic phase separation in VO2 films using He+ ion-implantation and infrared near-field imaging.

Findings

Nanoscale He+ ion-implantation induces anisotropic phase separation in VO2.

Infrared near-field imaging visualizes the cR-axis dependent anisotropy.

The method provides new insights into nanoscale phase behavior in strained oxides.

Abstract

Manipulating the strain induced poly-domains and phase transition in correlated oxide material are important for high performance devices fabrication. Though the electronic transport in the strained oxide film at macroscopic scales can be directly measured, the anisotropic electronic state and the controllable phase separation cross the insulator-to-metal transition within nanoscale size are still elusive. Here, we selected VO2 crystal film as a prototypical oxide and achieved the manipulation of anisotropy electronic phase separation via injecting He+ nanobeam into VO2 film at room temperature. In addition, this nanoscale phase separation was directly visualized by infrared near-field imaging measurements, showing the pronounced and unique cR-axis dependent anisotropy on VO2 surface. Our results offered new insights towards understanding the anisotropic nanoscale phase separation in strained metal oxide films.