A Minimal tight-binding model for ferromagnetic canted bilayer manganites

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Half-metallicity in materials is key for spintronics applications.
• Ferromagnetic manganites are promising candidates, though some exhibit minority-spin pockets.
• Understanding their electronic structure is crucial for material design.

Purpose of the Study:

• To develop robust tight-binding models for bilayer manganites.
• To describe the electronic band structure of majority and minority spin states.
• To investigate the role of bilayer coupling and orbital mixing in electronic properties.

Main Methods:

• Development of tight-binding models.
• Analysis of electronic band structure for various magnetic configurations (ferromagnetic, spin-canted antiferromagnetic, fully antiferromagnetic).
• Inclusion of bilayer coupling and Mn 3d orbital mixing effects.
• Consideration of kz dispersion.

Main Results:

• The models accurately describe the electronic band structure of bilayer manganites.
• Bilayer coupling and orbital mixing significantly influence bilayer splitting.
• The models account for subtle behaviors in spin states.

Conclusions:

• Tight-binding models provide a robust framework for understanding bilayer manganite electronic structures.
• Key parameters like bilayer coupling and orbital mixing are critical for achieving desired half-metallic properties.
• This work contributes to the rational design of materials for spintronics.