Dissipationless Anomalous Hall Current in the FerromagneticSpinel CuCr[sub2]Se[sub4-x]Br[subx].

In a ferromagnet, an applied electric field E invariably produces an anomalous Hall current J[subH] that flows perpendicular to the plane defined by E and M (the magnetization). For decades, the question of whether J[subH] is dissipationless (independent of the scattering rate) has been debated without experimental resolution. In the ferromagnetic spinel CuCr[sub2]Se[sub4-x]Br[subx], the resistivity ρ (at low temperature) may be increased by several decades by varying x (Br) without degrading M. We show that J[subH]/E (normalized per carrier, at 5 kelvin) remains unchanged throughout. In addition to confirming the dissipationless nature of J[subH], our finding has implications for the generation and study of spin-Hall currents in bulk samples. [ABSTRACT FROM AUTHOR]