Dynamics of magnetic domain wall motion after nucleation: Dependence on the wall energy

TL;DR

This study investigates how the energy of magnetic domain walls influences their motion after nucleation in a layered structure, revealing delays in domain expansion linked to wall energy effects during nanosecond magnetic pulses.

Contribution

It provides experimental insights into the role of domain wall energy in the dynamics of magnetic domain expansion in layered materials.

Findings

Delay in domain expansion due to wall energy effects.

Domain wall motion observed up to the Walker limit.

Influence of wall energy is significant for small domains.

Abstract

The dynamics of magnetic domain wall motion in the FeNi layer of a FeNi/Al2O3/Co trilayer has been investigated by a combination of x-ray magnetic circular dichroism, photoelectron emission microscopy, and a stroboscopic pump-probe technique. The nucleation of domains and subsequent expansion by domain wall motion in the FeNi layer during nanosecond-long magnetic field pulses was observed in the viscous regime up to the Walker limit field. We attribute an observed delay of domain expansion to the influence of the domain wall energy that acts against the domain expansion and that plays an important role when domains are small.