The extraordinary Hall effect of SrRuO3 in the ultrathin limit

We have measured the temperature dependence of the extraordinary Hall effect (EHE) in ultrathin films of the itinerant ferromagnet SrRuO3. We find that while the resistivity rho of the films varies significantly with their thickness, the EHE at low temperatures appears to be determined solely by rho. We discuss possible implications of this observation. (C) 2009 American Institute of Physics. [DOI: 10.1063/1.3073935]