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The effect of the Fe doping and the [110] poling on the optical and the photorefractive properties of the PZN-PT is investigated. The photorefractive properties were investigated by two-beam coupling experiments at a wavelength of 488 nm.

Fe-Co alloy thin films produced by direct current magnetron sputtering is studied to determine its structural and magnetic properties. Uniaxial magnetic anisotropy is exhibited by these films, and the easy axis is at right angles to the direction of incidence. Increase in sputtering gas pressure and increasing cobalt content at higher temperatures enhanced the sputtering field.

The magnetic and thermal characteristics of Fe-Zr-Co/Fe-Zr-Co-N multilayered thin films prepared by sputtering and electron cyclotron resonance plasma nitridation were investigated. The results showed that the incorporation of Co to the material dramatically increased its magnetic properties. The soft magnetic properties of the material exhibited excellent stability under heat treatment.

The low rare-earth content (RE) alpha-Fe/Nd(sub 2)Fe(sub 14)B nanocomposite magnets having a high soft phase ratio of Nd=6 at.% are fabricated by the rapid quenching method and the crystallization behavior, microstructure and magnetic properties of the ribbons in the annealing process are evaluated. The results show that an optimum rapid quenching rate exists and when compared with a completely amorphous state, the slight presence of clusters in as-melt-spun ribbons is favorable for obtaining good magnetic properties as the growth of alpha-Fe crystals is inhibited.

The photorefractive properties of the iron-doped Pb(Zn1/3Nb2/3)O3-PbTiO3 (PZN-PT) relaxor ferroelectric single crystals were investigated by two-beam coupling experiments. The Fe:0.01 wt %- and the Fe:0.1 wt %-doped 0.91PZN-0.09PT single crystals were grown with the flux solution method. The Extinction spectrum, the electro-opric coefficient, the light-induced absorption change, and the photoconductivity were measured in these samples. The maximum gain coefficient reached to 21 cm-1, which is about twice as large as that of undoped PZN-PT. The grating formation rate decreases with the Fe concentration. [ABSTRACT FROM AUTHOR]

An investigation was made of the magnetic properties of Nd-Fe-Co-V bulk exchange-spring magnets fabricated by spark plasma sintering and consisting of a hard Nd[sub 2]Fe[sub 14]B phase and a soft α-Fe phase and having a low rare-earth content of Nd = 2-7 at. %. The high saturation magnetization of the bulk exchange-spring magnets was confirmed experimentally, and the measured data agreed well with the saturation magnetization values estimated from their respective rare-earth content. The saturation magnetization values were nearly uniform and were not dependent on changes in the grain size. Additionally, the specific resistance of the samples nearly coincided with the values interpolated from the specific resistances of an ordinary sintered pure Fe bulk compact and a sintered Nd-Fe-B magnet. These results suggest that the α-Fe/Nd[sub 2]Fe[sub 14]B bulk exchange-spring magnets did not contain any appreciable grain boundary phase between the fine nanoscale-size grains or tertiary phase. [ABSTRACT FROM AUTHOR]

Analyses of InP involved a study of vapor phase epitaxial growth with halide as the transport agent. The study, conducted in sealed ampoules on earth and under microgravity, demonstrated the development of the S-doped InP layer. The shift of the disposition of the ampoules against a gravity field was accompanied by a massive shift in the thickness of the InP-grown layer on earth.

The spin-sprayed NiZn films are strongly promising to be turned into actual utilization to the noise suppressors for several GHz frequencies. The spin sprayed NiZn ferrite film exhibited not only strong magnetic loss but also weak reflection loss to be practically applied to noise suppressors operated up to several GHz.

The electromagnetic-noise suppression sheets made of Fe-Si-Al thin flakes embedded in polymer improve their noise suppressing performance in the magnetic field. The most interesting feature obtained here is the dc magnetic field, which is very effective to make loss profile extremely sharp suggesting a high potential of high performance noise suppressors for the Fe-Si-Al composite sheet.

The magnetic properties of low rare-earth content alpha-Fe/Nd2Fe14B bulk exchange-spring magnets were evaluated along with their potential as high-performance magnetic materials. The result reveals that bulk samples containing Nd in a range of 2-7 at. percent densified to approximately the same density as that of the master ingots and displayed magnetic properties equivalent to those of the starting powder ribbons following annealing.

Shielded current perpendicular to the plane spin valve heads with about 20 Gbit/in. dimensions is fabricated and tested both quasistatically and dynamically as a step prior to developing 200 Gbit/in heads. It is found that at least 2.1 % of the giant magnetoresistive ratio from the whole element is necessary to realize a head for the 200 Gbit/in. dimension.

A NiZn ferrite film (3 mm thick) was deposited at 90 °C by the spin-spray ferrite plating from an aqueous solution onto a 50 Ω microstrip line formed on an epoxy printed circuit board (PCB). A strong magnetic loss was caused by the ferrite film in a GHz range, δP[SUBloss] reaching 67% attenuation at 3 GHz, the upper limit of our measurement. Furthermore, the reflection loss was very weak, S[SUB11] being smaller than 7%. Thus plated NiZn ferrite films hold strong promise to be actually applied to a type of thin film electromagnetic noise suppressors; the films can be directly deposited onto noise sources (semiconductor elements or electronic circuits) to attenuate conducted-electromagnetic noises in the GHz range. Because the plated NiZn ferrite film was magnetically isotropic in film plane, the noise suppressors will be isotropic, attenuating noise electromagnetic waves radiated from any directions. The NiZn ferrite film was also plated on a flat glass substrate as a standard, which exhibited natural resonance frequency of f[SUBr] = 500 MHz and initial real permeability of μ' = 50. Compared to these values, the film on the PCB had higher f[SUBr] of 850 MHz, though reduced in μ' to 40. But the spectrum of the imaginary permeability μ'' shifted to a higher frequency range. This facilitated the strong magnetic loss at the high frequencies. The higher f[SUBr] for the film on the PCB may be attributed to the undulated columnar structure of the film which was observed by scanning electron microscopy. [ABSTRACT FROM AUTHOR]

Discusses a photoluminescence (PL) study made on an oxygen-containing silicon fine structure fabricated by a gas evaporation technique. Transmission electron microscope micrographs of the samples; Size of the crystalline portion; Data on the PL spectra taken from samples formed under various preparation conditions.

The photorefractive properties of the iron-doped Pb(Zn1/3Nb2/3)O3-PbTiO3 (PZN-PT) relaxor ferroelectric single crystals were investigated by two-beam coupling experiments. The Fe:0.01 wt %- and the Fe:0.1 wt %-doped 0.91PZN-0.09PT single crystals were grown with the flux solution method. The Extinction spectrum, the electro-opric coefficient, the light-induced absorption change, and the photoconductivity were measured in these samples. The maximum gain coefficient reached to 21 cm-1, which is about twice as large as that of undoped PZN-PT. The grating formation rate decreases with the Fe concentration. [ABSTRACT FROM AUTHOR]