The Hall resistivity ${\rho }_H$ and magnetoresistance of ${\mathrm{La}}_{1-x}{\mathrm{Ca}}_x{\mathrm{MnO}}_3$ ${(T}_c=265\mathrm{}$ K) have been measured at temperatures to 360 K in fields $H$ to 14 T. By comparing ${\rho }_H$ with the magnetization $M$, we have extracted the anomalous coefficient $R_s.$ We uncover an interesting relationship: $R_s$ is proportional to the zero-field resistivity from 200 to 360 K. Above $T_c,$ the Hall angle $\tan {\theta }_H\sim M$. Further, the effective Hall mobility is $H$ independent over a wide range of $H$. We contrast these scaling relations with the Hall effect in typical ferromagnets.

• Received 18 December 1997

DOI:https://doi.org/10.1103/PhysRevB.57.10248