The role of ferroelectric-ferromagnetic layers on the properties of superlattice-based multiferroics

TL;DR

This study investigates how ferroelectric and ferromagnetic layers in superlattices influence magneto-electric properties, revealing that ferroelectric layers significantly enhance magnetoresistance and coupling effects.

Contribution

It demonstrates the critical role of ferroelectric layers in enhancing magnetoresistance and magneto-electric coupling in superlattice structures compared to trilayers.

Findings

Ferroelectric layers enhance magnetoresistance at high magnetic fields.

Superlattices show stronger magneto-electric coupling than trilayers.

Absence of MR enhancement in trilayers indicates layer-dependent effects.

Abstract

A series of superlattices and trilayers composed of ferromagnetic and ferroelectric or paraelectric layers were grown on (100) SrTiO3 by the pulsed laser deposition technique. Their structural and magneto-electric properties were examined. The superlattices made of ferromagnetic Pr0.85Ca0.15MnO3 (PCMO) and a ferroelectric, namely Ba0.6Sr0.4TiO3 (BST) or BaTiO3, showed enhanced magnetoresistance (MR) at high applied magnetic field, whereas such enhancement was absent in Pr0.85Ca0.15MnO3/SrTiO3 superlattices, which clearly demonstrates the preponderant role of the ferroelectric layers in this enhanced MR. Furthermore, the absence of enhanced MR in trilayers of PCMO/BST indicates that the magneto-electric coupling which is responsible for MR in these systems is stronger in multilayers than in their trilayer counterparts.