Transition from Anomalous Hall Effect to Topological Hall Effect in Hexagonal Non-Collinear Magnet Mn₃Ga

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Antiferromagnetic materials offer potential for advanced electronic devices due to their unique spin properties.
• The anomalous Hall effect (AHE) and topological Hall effect (THE) are crucial phenomena for spintronic applications.

Purpose of the Study:

• To experimentally investigate the Hall effect in the non-collinear triangular antiferromagnet Mn3Ga.
• To explore the temperature dependence of the Hall effect and its relation to spin structure and symmetry.
• To assess the potential of Mn3Ga for spintronic and data storage devices.

Main Methods:

• Experimental observation of the Hall effect in Mn3Ga.
• Temperature-dependent measurements of anomalous Hall resistivity and conductivity.
• Analysis of spin texture and structural symmetry changes.

Main Results:

• Large anomalous Hall effect observed in Mn3Ga above 100 K, with resistivity increasing with temperature (1.25 μΩ·cm at room temperature).
• A temperature-independent topological Hall effect observed below 100 K (peak resistivity of 0.255 μΩ·cm).
• The topological Hall effect is linked to spin texture changes due to structural distortion from hexagonal to orthorhombic symmetry.

Conclusions:

• Mn3Ga exhibits significant anomalous and topological Hall effects.
• The observed phenomena are related to temperature-induced changes in spin texture and crystal symmetry.
• Mn3Ga is a promising material for antiferromagnetic spintronics and topological Hall effect-based data storage.