We have faburicated the electromagnet which can generate the magnetic pulse of the duration of microsecond range. This electromagnet has attached to a high-performance Kerr microscope system capable of real-time domain observation with the spatial resolution of 0.4㎛ and the Kerr angle resolution of 0.2° at × 500 magnification. Using this system, domain reversal dynamics of the Co/Pd multilayers in μs-scale time regime has been investigated by the direct domain observation and the magnetization reversal domain patterns with the magnetic field higher than the coercivity of the sample. The wall-motion speed and the nucleation rate were quantitively determined using the domain reversal model based on the time-resolved domain reversal patterns.
