Thin films of LaB6 were coated onto sapphire, Si and GaAs by electron-beam deposition. Superconductivity was not observed above 1.6K, and the anomalous magnetoresistance, associated with weak localization effects indicated that spin-orbit scattering rather than the magnetic impurity scattering was strong in this film. From detailed analysis of the magnetoresistance, it was estimated that the superconducting transition temperature of the sample was, if it existed, less than 40mK. It transpired that the parallel magnetoresistance was greater in magnitude than the perpendicular value. This large parallel magnetoresistance was beyond localization theory, and had never been observed in other materials.

Anomalous Magnetoresistance in LaB6 Thin Films. Terasaki, I., Uchida, S.I., Tajima, S., Uchinokura, K., Tanaka, S.: Journal of the Physical Society of Japan, 1990, 59[3], 1017-24