The measurement of magneto-optical Kerr effect of ultrathin films in a pulsed magnetic field

A Kerr rotation measurement system in a pulsed magnetic field (up to 11 T) was built to study magnetic properties of several ultrathin films. Our result shows that the Kerr rotation angle increases with the increasing wavelength of the incident light, while the difference between the spectras of Fe and CoFeAl is attributed to plasma resonance. We also studied the dynamic properties of the magnetic films: while ferromagnetic materials (Fe, CoFeAl, MnAs and CoMnAl) show quasi-static behavior in the time-scale of a few 100 μs, diamagnetic material GaAs shows time-dependent hysteresis.

► A Kerr rotation measurement system in a pulsed magnetic field has been built.
► The maximal field of 11 T and a short duration time of 1 ms of the pulse are achieved.
► The magneto-optical properties and spectra of various ultrathin films in the high magnetic field have been studied.
► The different results of the magnetic dynamic researches for ferromagnetic and diamagnetic materials have been presented.