Anomalous Hall effect of (formula presented) films with large magnetoresistance ratio: Evidence of Berry phase effect

The transverse Hall resistivity, (formula presented) and magnetization, M, of [110] and [100] oriented epitaxial (formula presented) films with large magnetoresistance were measured as a function of temperature and applied magnetic field to study the ordinary and spontaneous Hall coefficients. In the ferromagnetic regime, (formula presented) (formula presented) was found to be proportional to (formula presented) where (formula presented) is the spontaneous Hall coefficient, (formula presented) is the ordinary Hall coefficient, and (formula presented) is the core energy of the magnetic dipole. In addition, (formula presented) was found to be proportional to (formula presented) in the low-temperature regime (formula presented) where the ordinary Hall coefficient, (formula presented) is independent of temperature. A scaling behavior, (formula presented) was observed at high temperatures (formula presented) Hall effects of [110] and [100] oriented films are compared to each other. The results are discussed in terms of the exiting theories.