Large anisotropy in the paramagnetic susceptibility of SrRuO$_{3}$ films

By using the extraordinary Hall effect in SrRuO$_{3}$ films we performed measurements of the paramagnetic susceptibility in this itinerant ferromagnet, from $T_{c}$ ($\sim 150$ K) to $300$ K. These measurements, combined with measurements of magnetoresistance, reveal that the susceptibility, which is almost isotropic at $300$ K, becomes highly anisotropic as the temperature is lowered, diverging along a single crystallographic direction in the vicinity of $T_{c}$. The results provide a manifestation of the effect of large magnetocrystalline anisotropy in the paramagnetic state of a \textit{4d} itinerant ferromagnet [e-print: cond-mat/0311341]. They also shed light on the controversy regarding the nature of the universality class of the phase transition in SrRuO$_{3}$ [D. Kim \textit{et al}, Phys. Rev. B \textbf{67}, 100406(R) (2003)].