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The barium hexaferrite, BaFe12O19, microcrystals were obtained by the flux crystal growth method and were characterized by XRD, SEM, and TEM methods. XPS measurements were carried out on a powder sample. The binding energy differences between the O 1s and cation core levels, ΔBa= BE(O 1s) – BE(Ba 3d5/2) and ΔFe= BE(O 1s) – BE(Fe 2p3/2), were used to characterize the valence electron transfer on the formation of Ba–O and Fe–O bonds. The chemical bonding effects were considered on the basis of our XPS results measured for BaFe12O19and the earlier published structural and XPS data for other Ba- or Fe-containing oxide compounds. The band structure of BaFe12O19was calculated by spin-polarized DFT methods and compared to the valence band spectrum measured by the XPS method.

Nanocrystalline yttrium oxide (Y2O3) thin films were made by sputter deposition onto silicon (100) substrates keeping the deposition temperature fixed at 300 °C. The surface/interface chemistry, Y–O bonding, and optical constants of the Y2O3film surface and Y2O3–Si interface were evaluated by the combined use of X-ray photoelectron spectroscopy (XPS), depth-profiling, and spectroscopic ellipsometry (SE). XPS analyses indicate the binding energies (BEs) of the Y 3d doublet; i.e., the Y 3p5/2and Y 3d3/2peaks are located at 117.0 and 119.1 eV, respectively, characterizing yttrium in its highest chemical oxidation state (Y3+) in the grown films. The optical model is constructed based on the XPS depth profiles, which indicate that the Y2O3//Si heterostructure can be represented with Y2O3filmYxSiyOzinterfacial compoundSi substrate. Such a model accounts for the experimentally determined ellipsometry functions and accurately produces the dispersive index of refraction (n(λ)) of Y2O3and YxSiyOz. The n(λ) of Y2O3and YxSiyOzfollows Cauchy’s dispersion relation, while the YxSiyOzformation accounts for degradation of optical quality.

A new method of fabrication of a substrate for surface-enhanced Raman scattering (SERS) is proposed. The substrate is a layer of Ag nanoparticles on a solid surface, where the nanoparticles are synthesized by photo- or thermodecomposition of Langmuir−Blodgett layers of the silver salt of a fatty acid. The number of Ag nanoparticles depends on the number and composition of the monolayers. The optical properties and morphology of the substrate were studied by ultraviolet−visible absorption spectroscopy, scanning electron microscopy, and atomic force microscopy. It was found that the localized surface plasmon resonance has a maximum extinction in the range of 470−480 nm. The SERS ability was tested by use of a Langmuir−Blodgett film of hydroxamic acid.

The effect of 1.5 keV Arion irradiation on the (001) surfaces of potassium titanyl arsenate, KTiOAsO4(KTA), has been investigated using reflection high-energy electron diffraction (RHEED) and X-ray photoelectron spectroscopy (XPS). The (001) KTA surface is very sensitive to 1.5 keV Arion irradiation which induces significant structural modification in the top surface layers. The bonds in the KTA crystal lattice are relatively less unstable when compared to ; reduction of As5ions with the formation of As0and partial As loss from the top surface occurs with Arion irradiation. The formation of an unstable layer with chemically active and passive arsenic states may be a factor reducing the optical parameters and durability of nonlinear devices involving KTA.

Structural and electronic properties of the as‐grown (011) crystal face and the mechanically polished (001) surface of potassium titanyl phosphate (KTiOPO4or KTP) have been investigated by core‐level x‐ray photoelectron spectroscopy and reflection high‐energy electron diffraction (RHEED). With XPS analysis the original element binding energies, Auger parameters for K 2p3/2and P 2p core levels, relative element contents and valence band structure have been determined for both crystal cuts. A great depletion of O, K and P in the (011) face with respect to the (001) surface was discovered on comparison of element peak areas. The Ti 2p3/2peak areas were virtually the same for both cuts investigated. The relative element contents at the (001) surface were very close to the formal composition of KTiOPO4, so it is optimal to use the polished (001) KTP surface cleaned by ion bombardment and the Ti 2p3/2core level as standards for determination of the chemical composition of doped crystal surfaces. Copyright © 2002 John Wiley & Sons, Ltd.

Structural and electronic properties of the as-grown (011) crystal face and the mechanically polished (001) surface of potassium titanyl phosphate (KTiOPO4 or KTP) have been investigated by core-level x-ray photoelectron spectroscopy and reflection high-energy electron diffraction (RHEED). With XPS analysis the original element binding energies, Auger parameters for K 2p3/2 and P 2p core levels, relative element contents and valence band structure have been determined for both crystal cuts. A great depletion of O, K and P in the (011) face with respect to the (001) surface was discovered on comparison of element peak areas. The Ti 2p3/2 peak areas were virtually the same for both cuts investigated. The relative element contents at the (001) surface were very close to the formal composition of KTiOPO4, so it is optimal to use the polished (001) KTP surface cleaned by ion bombardment and the Ti 2p3/2 core level as standards for determination of the chemical composition of doped crystal surfaces. Copyright © 2002 John Wiley & Sons, Ltd.

Investigated are temperature dependence of dielectric constant and electrooptical properties strontium barium niobate ferroelectric layers made by HF technique in the phase transition region. Considered are peculiarities of polarization of the samples with small grain size (0.04 - 0.05 μ). Nonlinear properties of the films with large grain size (2 - 3 μ) are similar to corresponding properties of Ba0.5Sr0.5Nb2O6 crystal.

A study of forming strontium barium niobate thin films with the composition of Sr0.23Ba0.75Nb2O6 on the surface of a transparent electrode is presented. SBN films were grown by a high-frequency technique. The maximum value of the effective electrooptical coefficient was ref = |r33 - r13| ≃ 10-9 V/cm. The properties of SBN films conform well to those of monocrystalline samples.