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We investigate the Co thickness dependence of the structural and magnetic properties of Co thinfilm electrodes sandwiched between borate glasses in spin quantum cross (SQC) devices that utilize stray magnetic fields. We also calculate the Co thickness dependence of the stray field between the two edges of Co thin-film electrodes in SQC devices using micromagnetic simulation. The surface roughness of Co thin films with a thickness of less than 20 nm on borate glasses is shown to be as small as 0.18 nm, at the same scanning scale as the Cofilm thickness, and the squareness of the hysteresis loop is shown to be as large as 0.96-1.0. As a result of the establishment of polishing techniques for Co thin-film electrodes sandwiched between borate glasses, we successfully demonstrate the formation of smooth Co edges and the generation of stray magnetic fields from Co edges. Theoretical calculation reveals that a strong stray field beyond 6 kOe is generated when the Co thickness is greater than 10 nm at a junction gap distance of 5 nm. From these experimental and calculation results, it can be concluded that SQC devices with a Co thickness of 10-20 nm can be expected tofunction as spin-filter devices. [ABSTRACT FROM AUTHOR]

The effect of impurity and density on refractive index was studied for silica glasses synthesized with direct, sol-gel, and vapor phase axial deposition (VAD) processes. Linear relationships between the refractive index and density n=Cρ+D were found in a wide wavelength region from ultraviolet to infrared. The correlation coefficient C decreased from 0.081±0.007 cm3/g at 1.707 μm to 0.061±0.008 cm3/g at 0.238 μm. The relationship was different from those of the VAD or direct glasses formed by high-pressure densification, that is, the coefficient increased from 0.200±0.011 cm3/g at 1.707 μm to 0.229±0.012 cm3/g at 0.238 μm for VAD glass. Chlorine and hydroxyl impurities affected the refractive index; however, these impurities did not cause the linear relationship. After adjusting the index according to the chlorine related effect and the effect of the sample density, the difference between the sample’s refractive indices Δ(n2-1) showed a similar dispersion relation irrespective of the synthetic process. An analysis using a two-term harmonic oscillator model suggested that the origin of the refractive index dispersion is the oxygen 2p-silicon 3s interband transition, as is the dispersion relation of silica glass. The difference in the refractive indices in these synthetic silica glasses is deduced to be due to a stoichiometric excess or deficiency of oxygen atoms of forms ≡Si–OH HO–Si≡, ≡Si–Si≡, ≡Si––SI, etc., and the density arising from these forms in these synthetic processes. [ABSTRACT FROM AUTHOR]

A preliminary characterization of electrical properties for Al(500 nm)/LiGaO2(1000 nm)/ZnO(50 nm)/ScAlMgO4 (0001) (SCAM) structures, by forming 0.5 mm phis Al electrons, is presented. Heteroepitaxy of LiGaO2 is demonstrated on ZnO films, giving atomically sharp interface and fairly good exciton-related optical properties in the ZnO under layer.

Thin film of SrMoO3 on silica glass substrate by sputtering and the optical and electrical properties of the oxide films are studied. The plasma frequency due to free carriers is obtained by application of a Drude model to reflectivity values, which indicate that the effective mass of the conduction carrier is m(super *)= 2.1m(sub 0).

High-quality interface between an insulator and ZnO as a wide-band-gap semiconductor should realize devices based on field-effect carrier modulation or superlattices having large band offset over 1 eV. We demonstrate that LiGaO[SUB2] could be a possible candidate for this purpose. Heteroepitaxy of LiGaO[SUB2] is demonstrated on ZnO films, giving atomically sharp interface and fairly good exciton-related optical properties in the ZnO under layer. Although slight distortion of a basal-plane hexagon with a lattice mismatch of about 3% in LiGaO[SUB2] gives multidomain epitaxial structure with relaxed lattices, a possible solution is proposed to realize coherent heterointerface. [ABSTRACT FROM AUTHOR]

We used an rf magnetron reactive sputtering method to prepare SrMoO[sub 3] thin film on a silica glass substrate and evaluated its optical properties. The reflectivity of the blue-colored film showed a cutoff due to plasmon at ∼1.7 eV. From a Kramers–Kronig analysis of the reflectivity, the spectral dependence of dielectric constants and optical constants were obtained. They agreed in tendency with the constants determined by spectroscopic ellipsometry. The plasma frequency due to free carriers (4.5 eV) was obtained by application of a Drude model to reflectivity values, which showed that the effective mass of the conduction carrier was m[sup *]=2.1m[sub 0], where m[sub 0] is the free electron mass. © 2000 American Institute of Physics. [ABSTRACT FROM AUTHOR]