Localized Control of Curie Temperature in Perovskite Oxide Film by Capping-layer- induced Octahedral Distortion

TL;DR

This study demonstrates that a SrTiO3 capping layer can locally modify octahedral distortions in ultra-thin SrRuO3 films, leading to increased Curie temperatures and offering a new method for controlling functional properties in oxide materials.

Contribution

It introduces a lithographically patternable capping-layer technique to control octahedral rotations and magnetic properties in perovskite oxide films.

Findings

Curie temperature of SrRuO3 increased due to suppressed octahedral rotations

Local control of structural distortions achieved via lithographic patterning

Potential for developing functional oxide materials through capping-layer engineering

Abstract

With reduced dimensionality, it is often easier to modify the properties of ultra-thin films than their bulk counterparts. Strain engineering, usually achieved by choosing appropriate substrates, has been proven effective in controlling the properties of perovskite oxide films. An emerging alternative route for developing new multifunctional perovskite is by modification of the oxygen octahedral structure. Here we report the control of structural oxygen octahedral rotation in ultra-thin perovskite SrRuO3 films by the deposition of a SrTiO3 capping layer, which can be lithographically patterned to achieve local control. Using a scanning Sagnac magnetic microscope, we show increase in the Curie temperature of SrRuO3 due to the suppression octahedral rotations revealed by the synchrotron x-ray diffraction. This capping-layer-based technique may open new possibilities for developing functional oxide materials.