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Focuses on the structure and magnetic properties of iron-cobalt (Co) alloy films produced by direct current magnetron sputtering at an oblique angle of incidence. Overview of the uniaxial magnetic anisotropy in the film plane; Effect of increasing the anisotropy field on the sputtering gas and Co content; Surface morphology of the alloy films.

Anisotropic diffractive gratings formed by birefringent molecular alignment are fabricated by a holographic technique using a photo-cross-linkable liquid crystalline copolymer (PLCCP). Depending on the exposure energy used for holographic recording, bright or dark regions of the interference fringe can be chosen for the molecular-aligned region, analogous to positive- and negative-type photoresist processing in photolithography. In conjunction with simultaneously generated surface relief gratings, the anisotropic refractive index modulation inherent in the PLCCP film exhibits different diffraction properties depending on the incident beam polarization. The anisotropic refractive index grating profiles are quantitatively presented for two cases determined by the exposure energy, based on the Fourier analysis of diffractive optics. The selection of different grating formations selected by varying only the exposure energy could provide a strategy for the fabrication of functionalized diffractive optical elements. [ABSTRACT FROM AUTHOR]

We present a new fabrication method, called ‘two-step ultraviolet exposure’, to prepare anisotropic gratings in photocrosslinkable polymer liquid crystal films. Using the controllability of the reorientation direction of mesogenic molecules, anisotropic phase gratings, in which the mesogenic molecules were periodically modulated in orthogonal directions, were prepared by the use of one grating photomask. The resultant gratings diffract the light and convert the polarization states at the same time, and have applications as diffraction optical devices. [ABSTRACT FROM AUTHOR]

In order to examine the possibility of applying the HDDR process to segregated master ingots, Nd–Fe–B system HDDR powders were made from ingots with different levels of homogeneity, and their structures and magnetic properties were evaluated in detail. HDDR powders made from segregated as-cast ingots displayed anisotropy and large coercivity. They had a nearly homogeneous Nd2Fe14B phase, although some large areas with α-Fe and Nd-rich regions of 30 μm in size were present after the HD process. With increasing in the homogeneity level of the master ingots, the anisotropy of HDDR-processed powders decreased and their coercivity increased. In addition, an intermediate Ar treatment was applied between the HD and DR processes to improve the magnetic properties. As a result, the effect of the IA treatment was clearly confirmed, and good magnetic properties of Br=1.23 T, HcJ=848 kA/m and (BH)max=238 kJ/m3 were obtained. [Copyright &y& Elsevier]