Tuning the Magnetic Ground State by Charge Transfer Energy in SrCoO2.5 via Strain Engineering

TL;DR

This paper demonstrates how substrate-induced strain can modify the electronic and magnetic properties of SrCoO2.5 thin films by altering charge transfer energy and hybridization, enabling control over magnetic ordering.

Contribution

It reveals that strain engineering can tune the ground state and magnetic properties of SrCoO2.5 through changes in charge transfer energy and hybridization effects.

Findings

Strain induces a transition from antiferromagnetic to ferromagnetic ordering.

Charge transfer energy becomes negative under strain, affecting electronic structure.

Hybridization between O-2p and Co-3d bands is enhanced by strain.

Abstract

SrCoO2.5 (SCO) is a charge transfer insulator with 3d6 ground state configuration leading to antiferromagnetic nature. It is observed that substrate induced strain engineering modifies the ground state of SCO thin film with 3d7L (L:O-2p hole) configuration causing negative charge transfer energy.The consequent strong hybridization between O-2p and Co-3d bands causes a hole in O-2p band leading to hole mediated unconventional ferromagnetic ordering in SrCoO2.5 thin film. This opens up a new avenue to tune the electronic structure vis a vis magnetic property via strain engineering.