Magnetotransport properties of ferromagnetic Pr0.85Ca0.15MnO3/ferroelectric Ba0.6Sr0.4TiO3 superlattice films

TL;DR

This study investigates magnetotransport in ferromagnetic/ferroelectric superlattices, revealing significant magnetoresistance enhancements potentially due to magnetoelectric coupling, with implications for spintronic device development.

Contribution

It demonstrates increased magnetoresistance in Pr0.85Ca0.15MnO3/Ba0.6Sr0.4TiO3 superlattices with thicker ferroelectric layers, suggesting a novel magnetoelectric interaction mechanism.

Findings

Magnetoresistance increases with ferroelectric layer thickness.

Large MR observed cannot be explained by simple models.

Potential magnetoelectric coupling influences transport properties.

Abstract

Artificial superlattices designed with ferromagnetic Pr0.85Ca0.15MnO3 insulating layer and ferroelectric Ba0.6Sr0.4TiO3 layer were grown on (100) SrTiO3 substrates. The magnetotransport properties were measured with the current perpendicular to the plane geometry. An increase in magnetoresistance (MR), with no significant low field effect, was observed as the number of ferroelectric Ba0.6Sr0.4TiO3 layer thickness increases even up to 9 unit cells. For example, the superlattice [(Pr0.85Ca0.15MnO3)10(Ba0.6Sr0.4TiO3)9]25 shows 35 % MR at 100 K, though the Pr0.85Ca0.15MnO3 film was a robust insulator with negligible MR even at high applied magnetic field. This observed large MR cannot be explained by simple interfacial ferromagnetism or by the tunneling magnetoresistance. One possible explanation could be the effect due to the ferroelectric spacer layer and the associated magnetoelectric coupling.