  Magnetic topological semimetals, the latest member of topological quantum
materials, are attracting extensive attention as they may lead to
topologically-driven spintronics. Currently, magnetotransport investigations on
these materials are focused on anomalous Hall effect. Here, we report on the
magnetoresistance anisotropy of topological semimetal CeBi, which has tunable
magnetic structures arising from localized Ce 4f electrons and exhibits both
negative and positive magnetoresistances, depending on the temperature. We
found that the angle dependence of the negative magnetoresistance, regardless
of its large variation with the magnitude of the magnetic field and with
temperature, is solely dictated by the field-induced magnetization that is
orientated along a primary crystalline axis and flops under the influence of a
rotating magnetic field. The results reveal the strong interaction between
conduction electrons and magnetization in CeBi. They also indicate that
magnetoresistance anisotropy can be used to uncover the magnetic behavior and
the correlation between transport phenomena and magnetism in magnetic
topological semimetals.
