ABSTRACT
We have carried out an experimental investigation of the spin-wave dynamics in the Au/CoFeB/Au multilayer consisting of a ferromagnetic film with thicknesses of 0.8, 0.9 and 1.0 nm. We employed the Brillouin light scattering spectroscopy to measure the frequency of the spin waves in dependence on the wave vector. Additionally, we characterized the samples by ferromagnetic resonance measurements. We found that the considered samples exhibit perpendicular magnetic anisotropy with low damping, indicating small pumping effects. Furthermore, we found a nonreciprocal dispersion relation pointing at a non-negligible Dzyaloshinskii-Moriya interaction. These results make the Au/CoFeB/Au multilayer a compelling subject for further analysis and as a potential material for future applications within magnonics.
ABSTRACT
Co2Fe0.4Mn0.6Si (CFMS) and Co2FeGa0.5Ge0.5 (CFGG) Heusler alloys are among the most promising thin film materials for spintronic devices due to a high spin polarization, low magnetic damping and giant/tunneling magnetoresistance ratios. Despite numerous investigations of Heusler alloys magnetic properties performed up to now, magnetoelastic effects in these materials remain not fully understood; due to quite rare studies of correlations between magnetoelastic and other magnetic properties, such as magnetic dissipation or magnetic anisotropy. In this research we have investigated epitaxial CFMS and CFGG Heusler alloys thin films of thickness in the range of 15-50 nm. We have determined the magnetoelastic tensor components and magnetic damping parameters as a function of the magnetic layer thickness. Magnetic damping measurements revealed the existence of non-Gilbert dissipation related contributions, including two-magnon scattering and spin pumping phenomena. Magnetoelastic constant B11 values and the effective magnetic damping parameter αeff values were found to be in the range of - 6 to 30 × 106 erg/cm3 and between 1 and 12 × 10-3, respectively. The values of saturation magnetostriction λS for CFMS Heusler alloy thin films were also obtained using the strain modulated ferromagnetic resonance technique. The correlation between αeff and B11, depending on magnetic layer thickness was determined based on the performed investigations of the above mentioned magnetic properties.
ABSTRACT
We report on the Gilbert damping parameter α, the effective magnetization [Formula: see text], and the asymmetry of the g-factor in bottom-CoFeB(0.93 nm)/MgO(0.90-1.25 nm)/CoFeB(1.31 nm)-top as-deposited systems. Magnetization of CoFeB layers exhibits a specific noncollinear configuration with orthogonal easy axes and with [Formula: see text] values of [Formula: see text] kG and [Formula: see text] kG for the bottom and top layers, respectively. We show that [Formula: see text] depends on the asymmetry [Formula: see text] of the g-factor measured in the perpendicular and the in-plane directions revealing a highly nonlinear relationship. In contrast, the Gilbert damping is practically the same for both layers. Annealing of the films results in collinear easy axes perpendicular to the plane for both layers. However, the linewidth is strongly increased due to enhanced inhomogeneous broadening.
ABSTRACT
OBJECTIVE: The current study investigated the effect of culture on two factors implicated in the development of eating disorders, negative attitudes toward eating and dissatisfaction with body shape. METHOD: Hong Kong-born and Australian-born women from two Australian universities were surveyed using the Eating Attitudes Test (EAT) and the Figure Rating Scale (FRS). RESULTS: Results showed no difference between the groups in eating attitudes, but significant differences in body shape perceptions, with the Australian-born reporting greater dissatisfaction. Hong Kong-born subjects were separated into two groups based on their level of Chinese identity (Western acculturized and traditional). Their EAT and FRS scores were compared to the Australian-born, with Western acculturized Hong Kong-born subjects reporting significantly lower EAT and FRS scores than the Australian-born, whereas the more traditional Hong Kong-born subjects reported equivalent scores. DISCUSSION: Main implications center around the need for a cross-culturally sensitive definition of eating disorders, the effect of level of ethnic identity on eating attitudes and body image, and the importance of developing culturally appropriate measures.
