Charge transfer and interfacial magnetism in (LaNiO3)n/(LaMnO3)2 superlattices

TL;DR

This study investigates how charge transfer at interfaces in (LaNiO3)n/(LaMnO3)2 superlattices induces magnetism in LaNiO3 and affects their electronic properties, revealing a transition from metallic to insulating behavior with varying layer thickness.

Contribution

It demonstrates the controlled induction of interfacial magnetism and electronic phase transition in superlattices through precise layer thickness engineering.

Findings

Electrons transfer from LaMnO3 to LaNiO3, inducing magnetism.

Reduced LaNiO3 layer thickness causes a metal-insulator transition.

Interfacial magnetism correlates with electronic property changes.

Abstract

(LaNiO3)n/(LaMnO3)2 superlattices were grown using ozone-assisted molecular beam epitaxy, where LaNiO3 is a paramagnetic metal and LaMnO3 is an antiferromagnetic insulator. The superlattices exhibit excellent crystallinity and interfacial roughness of less than 1 unit cell. X-ray spectroscopy and dichroism measurements indicate that electrons are transferred from the LaMnO3 to the LaNiO3, inducing magnetism in LaNiO3. Magnetotransport measurements reveal a transition from metallic to insulating behavior as the LaNiO3 layer thickness is reduced from 5 unit cells to 2 unit cells and suggest a modulated magnetic structure within LaNiO3.