Revisiting galvanomagnetic effects in conducting ferromagnets

Area of Science:

• Condensed matter physics
• Spintronics
• Solid-state physics

Background:

• Galvanomagnetic effects, including anisotropic magnetoresistance (AMR) and planar Hall effect (PHE), are crucial phenomena in spintronics.
• Existing explanations for these effects can be complex and varied.

Purpose of the Study:

• To propose a unified and straightforward theoretical framework for understanding galvanomagnetic effects.
• To demonstrate how a specific coupling mechanism can explain both AMR and PHE.

Main Methods:

• Theoretical modeling based on the coupling between angular momentum density and magnetic moments.
• Derivation of general formulas for AMR and PHE from the proposed coupling.

Main Results:

• The proposed coupling naturally reproduces the established formulas for AMR and PHE.
• The model accounts for the possibility of 'negative AMR'.
• This coupling provides a unifying link to the anomalous Hall effect (AHE), previously shown to arise from the same mechanism.

Conclusions:

• The coupling between angular momentum density and magnetic moments offers a simple, unified explanation for AMR, PHE, and AHE.
• This theoretical approach simplifies the understanding of key spintronic phenomena.