Estimation of the resolution by MAMMOS read-out

The MAMMOS (magnetic amplifying magneto-optical system) read-out is achieved by applying an alternating external magnetic field for domain expansion and collapse processes. Since the read-out magnetic domain size is expanded by a magnetic field, a strong enhancement in the amplitude of the read-out signal is expected. The read-out laser power dependence of the MAMMOS signal was measured, and the resolution was estimated empirically. Applying an alternating magnetic field with suitable intensity, MAMMOS read-out was realized for a certain range of read-out laser power. The resolution and the margin of magnetic field depended on the laser power. Even at a 0.2 μ m domain size, its signal was recognizable without interference at the optimum laser power, A C/N level of over 50 dB was obtained for a 0.2 μ m domain size