Investigation of Phase Transitions in Ferromagnetic Nanofilms on a Non-Magnetic Substrate by Computer Simulation

Area of Science:

• Materials Science
• Condensed Matter Physics
• Computational Physics

Background:

• Ferromagnetic nanofilms exhibit unique magnetic properties influenced by their substrate.
• Understanding substrate effects is crucial for designing advanced magnetic materials.

Purpose of the Study:

• To investigate the impact of non-magnetic substrates on the magnetic properties of ferromagnetic nanofilms.
• To quantify the relationship between substrate-induced strain and the Curie temperature of nanofilms.

Main Methods:

• Utilized computer simulations employing the Frenkel-Kontorova potential to model substrate influence.
• Applied the Ising model and Metropolis algorithm to study magnetic properties and phase transitions.
• Analyzed the effects of varying substrate-to-film period ratios and film thickness.

Main Results:

• Substrate period mismatch induces film deformations, altering magnetic properties.
• Curie temperature increases with substrate compression and decreases with stretching, consistent across different film thicknesses.
• Non-unity coverage factors lead to atomic concentration variations in the first film layer, absent in subsequent layers.

Conclusions:

• Substrate-induced strain is a critical factor controlling the Curie temperature of ferromagnetic nanofilms.
• The observed phenomena are dependent on film thickness and substrate interaction parameters.
• First-layer atomic restructuring influences magnetic behavior, with effects diminishing in higher layers.