Ferromagnetism and metal-like transport in antiferromagnetic insulator heterostructures

TL;DR

This study demonstrates that layered heterostructures of antiferromagnetic insulators can exhibit ferromagnetism and metal-like transport properties due to interface effects and strain, revealing new ways to engineer magnetic and electronic behaviors.

Contribution

It introduces a method to induce ferromagnetism and metallic conduction in antiferromagnetic insulator heterostructures through interface engineering and strain effects.

Findings

Induced ferromagnetism at interfaces of heterostructures

Metal-like transport behavior observed in strained layers

Enhanced coercivity linked to layer thickness

Abstract

Strained Pr$_{0.5}$Ca$_{0.5}$MnO$_3$/La$_{0.5}$Ca$_{0.5}$MnO$_3$/Pr$_{0.5}$Ca$_{0.5}$MnO $_3$ trilayers were grown on (001)-SrTiO$_3$ substrates using the pulsed-laser deposition technique. The coupling at the interfaces of several trilayers has been investigated from magnetization and electronic transport experiments. An increase of La$_{0.5}$Ca$_{0.5}$MnO$_3$ layer thickness induces a magnetic ordering in the strain layers and at the interfaces leading to ferromagnetic behavior and enhanced coercivity, while resistivity shows metal-like behaviors. These effects are not observed in the parent compounds, which are antiferromagnetic insulators, opening a path, to induce artificially some novel properties.