Separation of the strain and finite size effect on the ferromagnetic properties of La_{0.5}Sr_{0.5}CoO_3 thin films

TL;DR

This study investigates how strain and finite thickness separately influence the ferromagnetic transition temperature in La_{0.5}Sr_{0.5}CoO_3 thin films, providing a method to distinguish these effects.

Contribution

It introduces a quantitative approach to separate strain and finite size effects on magnetic transition temperatures in epitaxial thin films.

Findings

Tensile strain suppresses the Curie temperature.

Compressive strain enhances the Curie temperature.

The method is applicable to other phase transitions in thin films.

Abstract

The ferromagnetic properties of epitaxial La$_{0.5}$Sr$_{0.5}$CoO$_3$ thin films have been studied. The magnetic transition is affected by both strain and finite thickness. We have used a series of films of different thickness and on different substrates in order to quantitatively determine the change in Curie temperature contributed by each effect. The phase diagram of T$_C$ versus in-plane strain suggests that the ferromagnetic transition temperature is suppressed by tensile strain and enhanced by compressive strain. The general method of separating strain and finite thickness effects should be applicable to any ordering phase transition in thin films.