Dissipation properties of anomalous Hall effect: Intrinsic vs extrinsic magnetic materials

Abstract

The power efficiency of Hall devices is still an open question. How is it possible to extract power from a current produced by the Hall effect? In what extent it is related to the nature of the effective magnetic field produced in the material? In order to answer these questions, a comparative study of anomalous Hall current injection and anisotropic current injection (through the planar Hall effect) are studied in Hall devices contacted to a lateral load circuit. Hall currents are injected into the load circuit from three different kinds of magnetic Hall bars: Mn5Si3 altermagnet, Co75Gd25 ferrimagnet, and Ni80Fe20 ferromagnet. The current, the voltage, and the power are measured as a function of the load resistance and the Hall angle. It is observed that the power dissipated for the three kinds of materials follows the same law as a function of load resistance and Hall angle, at the leading order in the Hall angle. Since the anomalous Hall effect in the altermagnetic Hall bar is due to the intrinsic topological structure (i.e., due to the presence of a Berry phase in the reciprocal space), these observations suggest that the dissipative properties of the anomalous Hall effect are dominated by the injection of electric charges accumulated at the edges, instead of the very mechanism responsible for it.