Magnetic Domain Patterns Depending on the Sweeping Rate of Magnetic Fields

TL;DR

This study investigates how the rate at which an external magnetic field is decreased influences the resulting magnetic domain patterns in thin ferromagnetic films through experiments and simulations.

Contribution

It demonstrates the dependence of domain pattern morphology on the field sweeping rate and discusses the underlying crystallization mechanism.

Findings

Rapid field decrease leads to sea-island domain structures.

Slow field decrease results in labyrinth domain structures.

Experimental and simulation results are consistent.

Abstract

The domain patterns in a thin ferromagnetic film are investigated in both experiments and numerical simulations. Magnetic domain patterns under a zero field are usually observed after an external magnetic field is removed. It is demonstrated that the characteristics of the domain patterns depend on the decreasing rate of the external field, although it can also depend on other factors. Our numerical simulations and experiments show the following properties of domain patterns: a sea-island structure appears when the field decreases rapidly from the saturating field to the zero field, while a labyrinth structure is observed for a slowly decreasing field. The mechanism of the dependence on the field sweeping rate is discussed in terms of the concepts of crystallization.