Anomalous Ferromagnetism in TbMnO3 Thin Films

TL;DR

This study reveals that TbMnO3 thin films exhibit intrinsic ferromagnetism at low temperatures, contrasting with the antiferromagnetic nature of bulk TbMnO3, and uses advanced scattering techniques to confirm the magnetic properties.

Contribution

The paper demonstrates that ferromagnetism in TbMnO3 thin films is intrinsic and not due to surface effects or impurities, providing new insights into the magnetic behavior of this material in thin film form.

Findings

TbMnO3 thin films show low temperature ferromagnetism.

The ferromagnetism is intrinsic to the film, not due to impurities.

Magnetometry and neutron scattering confirm the uniformity of magnetization.

Abstract

Magnetometry, x-ray, and neutron scattering have been used to study the structural and magnetic properties of a TbMnO3 thin film grown on a [001] SrTiO3 substrate by pulsed laser deposition. Although bulk TbMnO3 is a low temperature antiferromagnet, magnetometry measurements indicate the presence of low temperature ferromagnetism. Depth profiling by x-ray and polarized neutron reflectometry reveals a net sample magnetization that is commensurate with the film thickness, indicating that the observed ferromagnetism is not due to an altered surface phase (such as Mn3O4), or external impurities that might give rise to an artificial magnetic signal. Instead, these results show that the ferromagnetism is an intrinsic property of the TbMnO3 film.