Magneto-optical microscope magnetometer for simultaneous local probing of magnetic properties

The design of a magneto-optical microscope magnetometer (MOMM) for simultaneously probing local magnetic properties is described. The MOMM consists of an optical polarizing microscope capable of magneto-optical contrast that is used as a magnetometer by sweeping a magnetic field from an electromagnet. Due to full-field optical imaging, as opposed to single photodiode detection, the system is capable of simultaneous measurement of magnetic hysteresis loops and magnetization viscosity curves on 8000 individual local regions of 400×400 nm 2 area in ferromagnetic materials. The most striking feature of the system is that it provides two-dimensional maps of the local magnetic properties including the coercivity, the switching time, and the activation magnetic moment from two-dimensional arrays of the hysteresis loops and the viscosity curves. We present the local magnetic properties and their correlations in Co/Pd multilayer films prepared by electron-beam evaporation.