Realization of biferroic properties in La0.6Sr0.4MnO3 0.7Pb(Mg0.33Nb0.67)O3 0.3(PbTiO3) epitaxial superlattices

TL;DR

This study demonstrates the fabrication and characterization of La0.6Sr0.4MnO3 and Pb(Mg0.33Nb0.67)O3-PbTiO3 superlattices, revealing ferromagnetic behavior in all and ferroelectricity only in asymmetric structures, with interface effects playing a key role.

Contribution

It provides new insights into the magnetic and ferroelectric properties of epitaxial superlattices, highlighting the impact of interface and structural asymmetry on multiferroic behavior.

Findings

All superlattices showed ferromagnetism from 10K to 300K.

Only asymmetric superlattices exhibited significant ferroelectricity.

Magnetic field strongly influenced ferroelectric properties in asymmetric structures.

Abstract

A set of symmetric and asymmetric superlattices with ferromagnetic La0.6Sr0.4MnO3 and ferroelectric 0.7Pb(Mg0.33Nb0.67)O3 0.3(PbTiO3) as the constituting layers were fabricated on LaNiO3 coated (100) oriented LaAlO3 substrates using pulsed laser ablation. The crystallinity, magnetic and ferroelectric properties were studied for all the superlattices. All the superlattice structures exhibited a ferromagnetic behavior over a wide range of temperatures between 10K and 300K, whereas only the asymmetric superlattices exhibited a reasonably good ferroelectric behaviour. Strong influence of an applied magnetic field was observed on the ferroelectric properties of the asymmetric superlattices. Studies were conducted towards understanding the influence of conducting LSMO layers on the electrical responses of the heterostructures. The absence of ferroelectricity in the symmetric superlattice structures has been attributed to their high leakage characteristics. The effect of an applied magnetic field on the ferroelectric properties of the asymmetric superlattices indicated strong influence of the interfaces on the properties. The dominance of the interface on the dielectric response was confirmed by the observed Maxwell Wagner type dielectric relaxation in these heterostructures.