Direct observation of magnetic domain evolution in the vicinity of Verwey transition in Fe3O4 thin films

TL;DR

This study directly observes magnetic domain changes near the Verwey transition in Fe3O4 thin films, revealing domain evolution patterns and providing insights into the transition's magnetic mechanisms.

Contribution

It presents the first direct visualization of magnetic domain evolution near the Verwey transition in Fe3O4 thin films, linking domain behavior to transition mechanisms.

Findings

Stripe domains in Fe3O4/Mg2TiO4 film

Irregular domains in Fe3O4/MgO film

Domain behavior correlates with transition temperature and energy calculations

Abstract

We report a direct observation of magnetic domain evolution near the Verwey transition (TV) in Fe3O4 films. We found the stripe domains in the Fe3O4/Mg2TiO4 film while the irregular domains in the Fe3O4/MgO film and the similar characters of magnetic domains in the vicinity of TV for both samples: the bigger domain size and the higher contrast of the phase signal below TV and the more disordered domain images at TV. Remarkably, the magnetic behaviors can be well understood and the domain-wall energy and the demagnetizing energy can be calculated from the magnetic domains near TV in the Fe3O4/Mg2TiO4 film. Our work presents a demonstration of the low temperature magnetic domains and gives a new perspective to understand the Verwey transition in Fe3O4 thin films.