Distinguishing Local Demagnetization Contribution to the Magnetization Process in Multisegmented Nanowires

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Magnetic nanowires offer tunable properties for diverse applications.
• Stochastic magnetization switching is key for neuromorphic devices.
• Understanding magnetization reversal mechanisms in nanostructures is critical.

Purpose of the Study:

• To investigate the magnetization reversal process in multisegmented CoNi/Cu nanowires.
• To distinguish the contribution of individual segments to demagnetization.
• To analyze the stochastic nature of magnetization reversal in these nanostructures.

Main Methods:

• Utilized nonstandard 2D magnetic maps under in-plane magnetic fields.
• Correlated magnetic map data with magnetoresistance measurements.
• Employed micromagnetic simulations to complement experimental findings.

Main Results:

• Magnetization reversal occurs via multistep switching of individual CoNi segments, not a single Barkhausen jump.
• Confirmed the existence of vortex states through magnetoresistance and 2D MFM map analysis.
• Observed stochasticity due to variations in segment geometry/anisotropy and in repeated measurements.

Conclusions:

• Multisegmented CoNi/Cu nanowires display complex, stepwise magnetization reversal.
• The study elucidates the role of individual segments and stochasticity in magnetic nanostructure behavior.
• Findings provide insights for designing advanced magnetic materials for neuromorphic applications.