Field-Driven Magnetic Phase Diagram and Vortex Stability in Fe Nanometric Square Prisms

Area of Science:

• Condensed Matter Physics
• Materials Science
• Nanotechnology

Background:

• Understanding magnetic properties of iron (Fe) nanoprisms is crucial for developing advanced magnetic materials.
• Hysteresis and magnetic vortex states are key phenomena in nanomagnetism, influenced by size and shape.

Purpose of the Study:

• To investigate the zero-temperature hysteretic properties of iron quadrangular nanoprisms.
• To determine the size and aspect ratio conditions for the formation and stability of magnetic vortex states.
• To propose a field-driven magnetic phase diagram for these nanoprisms.

Main Methods:

• Utilized micromagnetic simulations employing the Object Oriented Micromagnetic Framework (OOMMF) via the Ubermag package.
• Solved the time-dependent Landau-Lifshitz-Gilbert equation to model magnetic dynamics.
• Calculated topological charge to characterize magnetic textures and analyzed aspect ratio dependencies.

Main Results:

• Identified specific aspect ratios and size conditions for stable magnetic vortex states along hysteresis loops.
• Developed a field-driven magnetic phase diagram illustrating vortex state stability.
• Analyzed the influence of aspect ratio on coercive force, nucleation, and annihilation fields.

Conclusions:

• The study provides insights into the formation and stability of magnetic vortex states in iron nanoprisms.
• Results align with experimental observations and other micromagnetic calculations, validating the proposed model.
• The developed phase diagram serves as a guide for designing nanomagnetic devices.