Tailored Magnetic Linear Birefringence in Wedge-Shaped Co Nanocluster Assemblies

The purpose of this paper is to present an experimental method to induce strong magnetic linear birefringence in two-dimensional assemblies of Co nanoclusters grown on glass plates. Additionally, we have also correlated the magnitude and characteristics of that nonlinear magneto-optical effect with the thickness and profile of those disordered nanostructures. For those aims, we have grown Co nanocluster assemblies on amorphous substrates, by means of pulsed laser ablation in off-axis geometry. This approach enabled us to obtain magnetic media with an intended and pronounced thickness profile, i.e., wedge-shaped assembly, to investigate the orientation and behavior of surface magnetization regarding both the thickness gradient direction and in-plane magnetic field. That study was accomplished by measuring the magneto-optical effects in reflection and transmission configurations, unveiling an out-of-plane magnetization whose magnitude depends closely on the thickness gradient direction. That component, arising from a graded magnetic anisotropy along the wedged nanostructure, adds a reversal mechanism to the surface magnetization, thus being responsible for the magnetic linear birefringence in our ultrathin Co assemblies.

FDTD simulation of electromagnetic wave propagation in magnetic randomly inhomogeneous media

An algorithm for the numerical simulation of the propagation of electromagnetic waves in randomly inhomogeneous magnetic media by the FDTD method has been developed. The formulated algorithm is suitable for analyzing the main timing characteristics, as well as identifying the features of the propagation of various types of signals in both time-independent and time-dependent layered randomly inhomogeneous media. The simulation of the propagation of the sine pulse, sine signal and square wave in time-independent magnetic randomly inhomogeneous media with a various levels of phase contrast of two types - with a “diffuse” distribution of inhomogeneities and their “close packing” is carried out. The influence of the concentration of magnetic granules and the type of their distribution on the characteristics of the transmitted and reflected signals is revealed.

FDTD simulation of electromagnetic wave propagation in magnetic randomly inhomogeneous media

An algorithm for the numerical simulation of the propagation of electromagnetic waves in randomly inhomogeneous magnetic media by the FDTD method has been developed. The formulated algorithm is suitable for analyzing the main timing characteristics, as well as identifying the features of the propagation of various types of signals in both time-independent and time-dependent layered randomly inhomogeneous media. The simulation of the propagation of the sine pulse, sine signal and square wave in time-independent magnetic randomly inhomogeneous media with a various levels of phase contrast of two types - with a “diffuse” distribution of inhomogeneities and their “close packing” is carried out. The influence of the concentration of magnetic granules and the type of their distribution on the characteristics of the transmitted and reflected signals is revealed.

FDTD simulation of electromagnetic wave propagation in magnetic randomly inhomogeneous media

An algorithm for the numerical simulation of the propagation of electromagnetic waves in randomly inhomogeneous magnetic media by the FDTD method has been developed. The formulated algorithm is suitable for analyzing the main timing characteristics, as well as identifying the features of the propagation of various types of signals in both time-independent and time-dependent layered randomly inhomogeneous media. The simulation of the propagation of the sine pulse, sine signal and square wave in time-independent magnetic randomly inhomogeneous media with a various levels of phase contrast of two types - with a “diffuse” distribution of inhomogeneities and their “close packing” is carried out. The influence of the concentration of magnetic granules and the type of their distribution on the characteristics of the transmitted and reflected signals is revealed.