Magnetization reversal in Fe(001) films grown by magnetic field assisted molecular beam epitaxy

TL;DR

This study investigates how applying a magnetic field during the growth of Fe(001) films affects their surface morphology and magnetic reversal behavior, revealing that the magnetic field influences domain structures and reversal mechanisms.

Contribution

It demonstrates the impact of an in-plane magnetic field on the morphology and magnetic reversal processes of Fe(001) films grown by molecular beam epitaxy.

Findings

Magnetic field influences surface step structure.

Magnetic properties are altered by in-field growth.

Magnetization reversal occurs via 90° domains.

Abstract

We studied the influence of a magnetic field (MF) on epitaxial growth and magnetic properties of Fe(001) films deposited on MgO(001). Thanks to modular sample holders and a specialized manipulator in our multi-chamber ultrahigh vacuum system, the films could be deposited and annealed in an in-plane MF of 100 mT. In situ scanning tunnelling microscopy showed that MF had a strong influence on the film morphology, and, in particular, on the structure of surface steps. The magnetic properties were studied ex situ using magneto-optic Kerr effect (MOKE) magnetometry and microscopy. We showed that the moderate in-plane magnetic field applied during growth has the visible impact on the magnetic properties. The observed angular dependence of the MOKE loops and domain structures were discussed based on a magnetization reversal model. In particular we found that magnetization reversal occurs via 90{\deg} domains and the reversal differs for the no-field and in-field grown samples, in correlation with the film morphology.