Micromagnetic modeling of magnetic domain walls in curved cylindrical nanotubes and nanowires

Metastable magnetic domain walls in cylindrical nanowires

The stability of the asymmetric domain wall (ATDW) in soft magnetic cylindrical nanowires and nanotubes is investigated using micromagnetic simulations. Our calculated phase diagram shows that for cylindrical permalloy nanowires, the transverse domain wall (TDW) is the ground state for radii below 20 nm whilst the Bloch point wall (BPW) is favoured in thicker wires. The ATDW stabilises only as ...

Observation of Bloch-point domain walls in cylindrical magnetic nanowires

Tunable remote pinning of domain walls in magnetic nanowires.

Domain wall (DW) pinning in ferromagnetic nanowires is in general a complex process. Distortions of the DW shape make quantitative agreement between modeling and experiment difficult. Here we demonstrate pinning using nanometer scale localized stray fields. This type of interaction gives well-characterized, tailorable potential landscapes that do not appreciably distort the DW. Our experimental...

Tunable conductance of magnetic nanowires with structured domain walls.

We show that in a magnetic nanowire with double magnetic domain walls, quantum interference results in spin-split quasistationary states localized mainly between the domain walls. Spin-flip-assisted transmission through the domain structure increases strongly when these size-quantized states are tuned on resonance with the Fermi energy, e.g., upon varying the distance between the domain walls w...

Micromagnetic simulations of magnetic domain wall dynamics

This summer project reproduces the foam experiment from previous summer but with oilwater emulsions. Increasing the viscosity of oil changes the droplets from soft to hard as well as the behavior from Newtonian liquid to granular matter. The expected outcome is Bachelor’s or Master’s Thesis or similar report depending on applicant’s background. The applicant is expected to have keen interest in...