Dimensional Control of Octahedral Tilt in SrRuO3 via Infinite-layered Oxides

TL;DR

This study demonstrates a novel method to control the magnetic properties of SrRuO3 by manipulating octahedral tilt through structural changes in adjacent SrCuO2 layers, revealing a new pathway for tuning quantum oxide heterostructures.

Contribution

It introduces a new approach to tune ferromagnetism in SrRuO3 by structural propagation from neighboring layers, focusing on oxygen coordination effects in infinite-layered oxides.

Findings

Structural transformation in SrCuO2 alters octahedral distortion in SrRuO3.

Changes in local structure modify Ru spin state and orbital hybridization.

Significant impact on magnetoresistance and Hall resistivity observed.

Abstract

Manipulation of octahedral distortion at atomic length scale is an effective means to tune the physical ground states of functional oxides. Previous work demonstrates that epitaxial strain and film thickness are variable parameters to modify the octahedral rotation and tilt. However, selective control of bonding geometry by structural propagation from adjacent layers is rarely studied. Here we propose a new route to tune the ferromagnetic response in SrRuO3 (SRO) ultrathin layers by oxygen coordination of adjacent SrCuO2 (SCO) layers. The infinite-layered CuO2 in SCO exhibits a structural transformation from "planar-type" to "chain-type" as reducing film thickness. These two orientations dramatically modify the polyhedral connectivity at the interface, thus altering the octahedral distortion of SRO. The local structural variation changes the spin state of Ru and hybridization strength between Ru 4d and O 2p orbitals, leading to a significant change in the magnetoresistance and anomalous Hall resistivity of SRO layers. These findings could launch further investigations into adaptive control of magnetoelectric properties in quantum oxide heterostructures using oxygen coordination.