Nanometer Scale Hard/Soft Bilayer Magnetic Antidots.

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Nanoporous structures significantly alter the magnetic properties of thin films.
• Understanding the interplay between nanopore geometry and magnetic behavior is crucial for advanced magnetic devices.

Purpose of the Study:

• To analyze the effect of nanometer-scale pores on thin film magnetic properties.
• To investigate how the out-of-plane magnetization component from nanopores influences in-plane magnetic behavior in patterned hard/soft magnetic thin films.
• To compare the influence of disordered and ordered antidots on magnetic coupling in Co/Py bilayers.

Main Methods:

• Magneto-optical Kerr effect (MOKE) and first-order reversal curve (FORC) techniques were employed to probe magnetic behavior.
• Magnetic force microscopy (MFM) was used for imaging the magnetic structures.
• Analysis focused on Co/Py bilayers with antidot arrays of 35-nm diameter.

Main Results:

• Ordered antidots generated a stronger out-of-plane magnetization component compared to disordered ones.
• This induced perpendicular magnetization influenced the hard layer's in-plane magnetic behavior similarly for thin or absent soft layers.
• The influence varied with a thicker soft layer, suggesting potentially weaker coupling.

Conclusions:

• The arrangement of nanopores (ordered vs. disordered) critically affects the induced out-of-plane magnetization.
• The magnetic coupling in Co/Py bilayers is modulated by the nanopore-induced perpendicular magnetization component.
• The thickness of the soft magnetic layer plays a significant role in the observed magnetic coupling behavior.