A versatile method for the exploration of magnetooptical properties of polar saturated and unsaturated ferromagnetic metallic thin films

Polar unsaturated ferromagnetic thin films are promising for low-power and high-speed nonvolatile resistive and optical memories. Here we measure the magnetooptical (MO) response of polar unsaturated Co 90 Fe 10 and Co 40 Fe 40 B 20 thin films in the spectral range from 400 nm to 1000 nm using vector MO generalized ellipsometry (VMOGE) in an out-of-plane applied magnetic field of ±0.4 T where magnetization of the ferromagnetic (FM) thin film is not saturated. Using magnetooptical simulation software (MagOpS ® ), we extract the complex MO coupling constant ( Q ) of the polar unsaturated FM thin films from difference spectra of VMOGE data recorded in a polar configuration at H z = +0.4 T and H z = −0.4 T. The presented approach opens a path to determine Q of both polar saturated and polar unsaturated FM thin films for simulating the MO properties of application-relevant optical memory multilayer structures.