Sharai I. Influence of structural inhomogeneities on the surface of the magnetic films on their magnetic and optical properties

The thesis is devoted to the study of influence of structural inhomogeneities on the surface of the magnetic films on their magnetic and optical properties. In particular, the investigations of ultra-thin magnetic films layers of bismuth-substituted ferrite garnets and one-dimensional magnetophotonic crystals were performed. It was found that a high-energy ion treatment of substrates surface leads to the formation of a transitional layer on the boundary between substrate and film with a smooth change of composition that enables to control the magnitude of magneto-optical effects in such films. This changes the compensation point of the magnetic sample, as well as magnitude and sign of magneto-optical effect. It was experimentally demonstrated that the effectiveness of recrystallization and the roughness of NiFe films surface when irradiated by nanosecond laser pulses depends on the laser radiation wavelength. For the first time, the method of managing of high-frequency magnetic susceptibility of magnetic nanoparticles by using an external constant magnetic field for their heating by an alternating magnetic field was developed. It was shown that varying the magnitude and direction of the constant magnetic field, we can change the values of high-frequency magnetic susceptibility by dozen times. The phenomenon of nonlinear dependence of magnetic permeability on the magnetic field was proposed to use for the creation of high-sensitive compact flux-gate magnetic field sensors with parametric amplification of signals. The methods of creation of high-gradient magnetic fields with a given configuration using structured substrates were proposed.