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Atom probe tomography and secondary ion mass spectrometry were used to investigate the effects of carbon (C) co-implantation and subsequent annealing at 600 to 1200 °C on the behavior of implanted boron (B) atoms in silicon. When B alone was implanted, annealing at 600 to 800 °C caused it to form clusters in the peak region (1020 cm−3) of the concentration profile, and diffusion only occurred in the low-concentration tail region (<1018 cm−3), which is thought to be the well-known transient enhanced diffusion. However, when co-implantation with C was performed, this diffusion was almost completely suppressed in the same annealing temperature range. In the absence of C implantation, annealing at 1000 °C caused B clusters to begin to dissolve and B to diffuse out of the peak concentration region. However, this diffusion was also suppressed by C implantation because C atoms trapped B atoms in the kink region found at the B concentration level of 2 × 1019 cm−3. At 1200 °C, B clusters were totally dissolved and a strong B diffusion occurred. In contrast to lower annealing temperatures, this diffusion was actually enhanced by C implantation. It is believed that Si interstitials play an important role in the interaction between B and C. This kind of comprehensive investigation yields important information for optimizing ion implantation and annealing processes. [ABSTRACT FROM AUTHOR]

The nematic liquid-crystal direction-orientations in the vicinity of the interface between a liquid-crystal layer and a glass substrate is evaluated in various orientations under an applied electric field, using shear horizontal (SH) wave propagation. This was done in relation to acoustic phase delay change in the cell structures.

The decay curves of the photoinduced transient thermoelectric effect (TTE) in bismuth single crystals exhibits multiple relaxation processes for photogenerated electrons and hole thermal diffusion. Mobility, mass and electronic properties of carriers are evaluated from the relaxation periods.

The measurement of magnetic nonlinear-optical effects in tangential configurations of the magnetic field application in Bi-doped yttrium-iron-garnet (Bi:YIG) magnetophotonic microcavity is discussed. The magnetization-induced variation of the second-harmonic (SH) intensity in transversal configuration is observed with magnetic contrast up to 0.3.

The fabricated three-dimensional magnetophotonic crystals (3D MPCs) based on artificial opals are examined. Magnetic properties of the substances embedded in the opal lattice are observed in the opal-magnetite and opal-garnet composites.

The magneto-optic spatial light modulator (MOSLM) driven by an electric field, achieved by using the electrostrictive effect of [Pb(Zr(sub 0.52)Ti(sub 0.48))O3] (PZT) thin films, is described. The MOSLM overcomes the thermal problems of the conductors that occur in the current-addressed driving method, and provides high frame rates because of the high speed of the PZT thin film, and higher resolution due to a simpler conductor structure.

The switching properties of the grooved pixels are investigated magneto-optically. Optimally grooved pixels allow the use of high amounts of bismuth in the garnet film, and it is very effective in reducing the driving-current of the magneto-optic spatial light modulator (MOSLM) due to a low switching threshold field.

The effect of magnetic field on the electrode potential of Fe, Co, Ni and Cu in different electrolytes is examined. A proportional change in the potential of the ferromagnetic iron electrode in solutions of iron (III) chloride and nitrate, and caustic soda was caused by the magnetic field.

A study was conducted to analyze the magnetic characteristics of multilayer films featuring FeRhIr, AG and Fe layers. Changes in the pinning strength of magnetization in antiferromagneic and ferromagnetic phases of FeRhIr layers with a magnetic field were examined. The magnetostrictive response of the film was determined by applying a magnetic field up to 100 Oe. Results showed that increases in temperature correlates to the association of the phase transition of FeRhIr layers with the release of magnetization pinning.

We have investigated valence band and conduction band electronic structures and interfacial chemical bonding states of nitrogen-plasma-treated HfSiON/SiON gate stacks on Si substrates with and without rapid thermal annealing by photoelectron spectroscopy and x-ray absorption spectroscopy to correlate them with electrical properties. We have found that the N3 component in N 1s can be correlated with electron trapping. Photoelectron spectra and O K-edge absorption spectra confirm the existence of the SiO2-rich phase-separated area in HfSiON films. Band offsets for the HfSiON/Si and the SiO2-rich HfSiON/Si are determined to be 2.5 and 4.2 eV for valence band and 1.7 and 3.6 eV for conduction band, respectively. [ABSTRACT FROM AUTHOR]

By utilizing a sharp magnetic needle made of a sintered Nd2Fe14B permanent magnet, we were able to produce a strong magnetic field of up to approximately 560 kA/m in a transmission electron microscope and succeeded in observing the magnetization reversal in a thin film of sintered Nd2Fe14B by in situ Lorentz microscopy. The increase in the magnetic field induced by the magnetic needle led to a pair of straight magnetic domain walls forming abruptly from the grain boundary. The successive nucleation in the neighboring grain started at the grain boundary adjacent to the magnetic domain wall formed first. Eventually, the magnetic domain walls in the neighboring grains connected and moved continuously and finally disappeared. [ABSTRACT FROM AUTHOR]

Surface potential and the amount of charging on an insulator surface under electron beam irradiation have been quantitatively measured. For these measurements, a special sample holder was developed. The surface potential was measured using a secondary electron method. The measurement of the surface potential revealed that the sample behaves as a resistor, enabling the present technique to be applied for mapping microarea resistance. The results of measuring the amount of charging revealed that the amounts of charging obtained with different beam currents are the same in spite of different surface potentials. This strongly suggests that the charging phenomenon depends on the distribution of the charge trapping sites. [ABSTRACT FROM AUTHOR]

Propagation characteristics of the zeroth-order symmetric (S[sub 0]) mode shear-horizontal (SH) wave in a cell structure containing a thermotropic liquid crystal layer with chiral smectic-C (SmC[sup *]), smectic-A (SmA), chiral nematic (N[sup *]) and isotropic (Iso) phase states, are examined. The SH wave propagation is numerically analyzed with consideration of the directional dependence of the viscosity and elastic constant of the SmA liquid crystal. Temperature dependencies of acoustic phase delay and propagation loss of the SH wave are observed. The critical behavior of the acoustic phase delay and the propagation loss of the SO mode SH wave in the vicinity of the N[sup *]-SmA phase transition temperature are explained by the existence of the elastic constant related to layer compression. The layer compression elasticity is predominant in the SmA phase, and is determined from the comparison of numerical analysis with experimental results. [ABSTRACT FROM AUTHOR]

Several studies are conducted to explain the magnetic properties of the various polycrystalline magnetic garnets that are used for voltage driven type magneto-optic spatial light phase modulators. The magnitude and the linearity of the stress is shown to be completely dependent on the static bias field and magnetostriction constant.

The article explains the fabrication, characteristics and the properties of the various one-dimensional magnetophotonic crystals. These crystals are shown to be widely used for enhancing the magneto-optic properties of the magneto-optic spatial light phase modulator.

The optical and magneto-optical properties of bismuth-substituted yttrium iron garnet (Bi:YIG) films with Au nanoparticles dispersed on their top surfaces are studied. Polarization-resolved transmission spectra have shown that the rotation is due to anisotropy of light propagation through the array of Au nanoparticles.

The optic and magneto-optic properties of the magnetophotonic crystal for reflection-type magneto-optic spatial light modulators are examined. The surface reflection has affected the reflection-type magnetophotonic crystal (R-MPC) on Kerr rotation and reflectance.

One-dimensional magnetophotonic crystal (MPC) is combined with micropatterned drive lines in order to develop thin-film-type magneto-optical spatial light modulator. A large enhancement is found in the Faraday rotation by using MPC and a trade-off relationship is observed in the optimization of the repetition number of the dielectric multilayer and the multiple number of the magnetic defect layer in the MPC.

The structural and magnetic properties of monolayer film of the CoPt nanoparticles are reported. The monolayer film of CoPt nanoparticles is fabricated by the application of APTS as a coupling layer to find that the grain growth is well controlled even after annealing at higher temperatures.

The conditions for partially coating SiO2 spheres with ferrite for three-dimensional magneto-photonic crystals are discussed. The ratio of Fe(super 3+)/Fe(super 2+) in the range of 50 percent to 100 percent and the pH value in the range of 8-10 is essential for the synthesis of sphere coated with Fe3O4 fine particles of 20 nm diameter.

The structural, magnetic, magnetotransport, optical and magneto-optical characteristics of (FePt)(sub 1-x)(SiO2)x thin films in as-deposited state and after annealing are explored. The disorder-order phase transitions in FePt granules, changes in the mean granular size and alloy microstructure leads to the magneto-optical spectra transformation after annealing.

Successful coating of three types of ferrites uniformly onto a resinous substrate with spiral structure prepared by stereolithography is discussed. It is reported that magnetite coated machines have biocompatibility and small density.

The effects of groove depth of magnetic garnet pixels and existence of patterned permalloy assist film on the magnetization switching characteristics of elements are explored. The combinatory use of the pixel groove control and the patterned permalloy assist film is effective for reducing the switching field of magnetic garnet pixels. The results show that the magnetization field to switch a structured pixel could be reduced by controlling the pixel groove depth.

The magneto-optical (MO) imaging is one of the methods for visualizing the magnetization distribution corresponding to the leakage magnetic fields. In general, the MO imaging requires high-spatial resolution and high-contrast imaging. The spatial resolution of the MO imaging depends on the magnetic domain size. In this study, we used the polycrystalline garnet films with a domain size of about 50 nm for the high-resolution imaging. We also demonstrated MO imaging using the magnetophotonic crystal (MPC) with polycrystalline garnet films in order to improve the MO image contrast. The MO images of a carbon steel surface can be observed by means of the MPC. As a result, the high-spatial resolution and high-contrast MO image was obtained by MPC. [ABSTRACT FROM AUTHOR]

This article reports the preparation of submicrometric magnetic particles which are promising parts for fabrication of three-dimensional magneto-photonic crystals. In our experiments SiO2 spheres with diameter of about 260 nm were coated with Fe3O4 fine particles from an aqueous solution at room temperature. It is found that spheres coated with Fe3O4 fine particles with a diameter of about 20 nm are synthesized when the ratio of Fe3+/Fe2+ is in the range 50%–100% and the pH value is in the range 8–10. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Structural, magnetic, magnetotransport, optical, and magneto-optical properties of (FePt)1-X(SiO2)X thin films in as-deposited state and after annealing were investigated. Magneto-optical properties were measured in the transversal Kerr effect (TKE) geometry. Magneto-optical spectra in nanocomposites (FePt)1-X(SiO2)X depend greatly on volume fraction of metal and annealing conditions. The TKE reaches the maximum value for compositions close to the percolation threshold X≈57% in as-deposited samples, as well as a maximum of the magnetoresistance. After annealing at 700 °C the TKE value significantly increases and the maximum of the magneto-optical response is observed at X≈70%. The magneto-optical spectra transformation after annealing is mainly due to the disorder-order phase transitions in FePt granules, changes in the mean granular size, and alloy microstructure. The TKE spectra calculated in the framework of the effective medium approximation for as-deposited samples are in good agreement with the experiment. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A magneto-optic spatial light modulator driven by an electric field is fabricated by using the electrostrictive effect of [Pb(Zr[SUB0.52]Ti[SUB0.48])O[SUB3]] (PZT) thin film. As the stress field induced by the PZT thin film reduces the anisotropy energy of the structured garnet film, we find that the pixels can be easily switched in accordance with or without the small external bias field. When peak-to-peak 8 V at the X and Y conductors is applied with the external bias field of 40 Oe at the fabricated device, the selected pixel is switched independently. [ABSTRACT FROM AUTHOR]

We fabricated a one-dimensional magnetophotonic crystal (MPC), in which a magnetic layer of Co–ferrite (∼40 nm in thickness) is sandwiched by a couple of dielectric multilayer reflectors with (SiO[sub 2]/TiO[sub 2])×7 structure. The Co–ferrite layer was synthesized by ferrite plating from aqueous solution at 90 °C. The MPC is so designed to enhance magneto-optical Faraday rotation θ[sub F] at the Fabry–Pe´rot resonance wavelength λ of the multilayer structure. θ[sub F] was observed to increase by factor of ∼5.4, but at λ=∼620 nm which is deviated from the target resonance (λ=740 nm) and at very weak transmissivity. This may be because the Co–ferrite layer is rough in surface and smaller in thickness than the target thickness at which Fabry–Pe´rot resonance is designed to occur. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Structural, magnetic, magnetotransport, optical, and magneto-optical properties of (FePt)1-X(SiO2)X thin films in as-deposited state and after annealing were investigated. Magneto-optical properties were measured in the transversal Kerr effect (TKE) geometry. Magneto-optical spectra in nanocomposites (FePt)1-X(SiO2)X depend greatly on volume fraction of metal and annealing conditions. The TKE reaches the maximum value for compositions close to the percolation threshold X≈57% in as-deposited samples, as well as a maximum of the magnetoresistance. After annealing at 700 °C the TKE value significantly increases and the maximum of the magneto-optical response is observed at X≈70%. The magneto-optical spectra transformation after annealing is mainly due to the disorder-order phase transitions in FePt granules, changes in the mean granular size, and alloy microstructure. The TKE spectra calculated in the framework of the effective medium approximation for as-deposited samples are in good agreement with the experiment. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]