Identifying magnetic phases in chemically ordered and disordered FeAl thin films

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Direct magnetic writing offers a novel approach for fabricating nanoscale elements for data storage and spintronics.
• Fe60Al40 thin films exhibit distinct magnetic phases upon local chemical disordering, creating nanoscale regions with varying magnetization and coercivity.

Purpose of the Study:

• To investigate the magnetic properties and interaction mechanisms of coexisting nanoscale magnetic phases in Fe60Al40 thin films.
• To understand the influence of chemical ordering on the magnetic behavior of these films for potential spintronic applications.

Main Methods:

• Fabrication of Fe60Al40 thin films.
• Inducing local chemical disordering via irradiation to create distinct magnetic phases (non-irradiated ferromagnetic area - NIFM and irradiated ferromagnetic area - IMF).
• Characterization of magnetic properties and interaction mechanisms between coexisting phases.

Main Results:

• Adjacent nanoscale regions with different magnetic properties (low-magnetization/high-coercive NIFM and high-magnetization/low-coercive IMF) were formed.
• Evidence of exchange-spring behavior was observed, although direct exchange coupling was generally absent.
• Both magneto-structural phases displayed spin-glass-like properties at low temperatures.

Conclusions:

• Chemical ordering significantly influences the magnetic properties of Fe60Al40 films.
• The observed magnetic behaviors, including exchange-spring and spin-glass properties, are critical for advancing spintronic device functionality.
• Controllable magnetic properties in alloys are achievable through understanding and manipulating chemical ordering.