Materials Literature
按标题、摘要、年份、主题和来源检索公开元数据。结果保留作者、摘要、分类与原始来源链接。
A well-ordered surface layer of Ca on ${\mathrm{TiO}}_{2}(110)$ has been prepared by forcing Ca impurities from the bulk to segregate to the surface during annealing. The surface was studied by scanning tunneling microscopy (STM), Auger electron spectroscopy, low-energy electron diffraction, reflection high-energy ele…
One of most important issues of magnets for automobiles is thermal stability. The aim of the present work is to make clear the available temperature limit of sintered and bonded magnets for automobile applications. Thermal stability was determined by the critical temperature of 3% irreversible flux loss (T−3%φ) under…
We report on the growth of epitaxial La2/3Sr1/3MnO3 thin films on buffered Si(001) substrates. We show that a suitable choice of the buffer heterostructure allows one to obtain epitaxial (00h), (0hh), and (hhh) manganite thin films. The magnetotransport properties are investigated and we have found that the low-field…
The effects of yttria stabilized zirconia (YSZ) buffer layers for the sol-gel derived Ni–Zn ferrite thin films on SiO2/Si(100) substrates were investigated. The 500 Å thick YSZ buffer layers were found to effectively suppress the diffusion of Si into the ferrite thin films. As a consequence, films with lower Hc and hi…
Pure and ZnTi-doped spherical barium ferrite particles were prepared using two different methods: semicoprecipitation and ultrasonic spray pyrolysis. The ultrasonic spray pyrolysis method was more effective in controlling particle shape. Particle size was in between 0.27 and 0.3 μm. Coercivity and saturation magnetiza…
The structure of the hydrogen terminated, $(2\ifmmode\times\else\texttimes\fi{}1)$ reconstructed diamond (100) surface has been investigated by low-energy electron-diffraction (LEED) intensity versus energy $[I(E)]$ measurements in combination with tensor LEED calculations. It has been found that the surface correspon…
We present an analysis of recent thermal-conductivity measurements on crystalline silicon in which the concentration of the ${}^{28}\mathrm{Si}$ isotope has been increased above the natural abundance. We calculate from the phonon Boltzmann equation the change in the conductivity due to a change in isotope concentratio…
The spin and orbital contribution to the total magnetization have been measured in NiO by exploiting the polarization dependence of nonresonant x-ray magnetic scattering. Although the orbital moment is usually neglected, we observed that the orbital moment actually plays an important role with a contribution of 17% to…
We compare infrared absorption and Raman spectra of high-quality ${\mathrm{Ge}}_{1\ensuremath{-}x}{\mathrm{Si}}_{x}$ bulk crystals $(0<x<0.4).$ We use this comparison together with lattice-dynamical calculations to report on the behavior of the Ge-Ge phonon at 300 ${\mathrm{cm}}^{\mathrm{\ensuremath{-}}1}$, to i…
SmCo based films, ≈1–3 μm thick, have been directly crystallized onto moderately heated polycrystalline susbstrates, 375 °C, by high pulse energy pulsed laser deposition. Films have been deposited to compare shadow and direct deposition. Only for shadow deposition conditions has it been possible to deposit CaCu5-type…
Energy transfer processes from Yb3+ to Tm3+ ions have been investigated in various fluoride microcrystals to examine the application limit of a simple rate equation model and to obtain methods for characterizing the host materials as to energy transfer. It has been shown that the energy transfer coefficients from dono…
A series of [La2/3Ca1/3MnO3/La1/3Ca2/3MnO3]15 multilayers, with bilayer thicknesses between 2 and 32 nm, has been prepared by pulsed laser deposition. The study of their magnetic and magnetotransport properties reveals, for the first time in this category of materials, the presence of an exchange biasing mechanism at…
The electronic structures of ${\mathrm{Nd}}_{1\ensuremath{-}x}{\mathrm{Sr}}_{x}{\mathrm{MnO}}_{3}$ with $x=\frac{1}{2}$ (high- and low-temperature phases) and $x=\frac{9}{16}$ were studied by using the rotation-invariant local spin density approximation (LSDA)+U formalism in the framework of the linear-muffin-tin orbi…
Magnetization curves up to 25 T at 4.2 K are reported for mixed-valence manganites (R0.7A0.3)MnO3. All the R=La compounds show an extrapolated ferromagnetic moment of ∼3.4 μB/f.u. The A=Sr and Ca compounds show essentially no high-field slope, dM/dB&lt;0.001 μB/T whereas the Pb and Ba compounds show slopes of 0.00…
The electronic structures in chiral carbon nanotubes are obtained by using the Su-Schrieffer-Heeger model with the Coulomb interaction included. The periodic boundary condition is applied for the direction of the tubular axis. The third-order polarizabilities of chiral carbon nanotubes are calculated by using the elec…
We systematically study transport and optical properties of charge-transfer salts, (Me 2 -DCNQI) 2 Li 1- x Cu x (0≤ x ≤1). The temperature dependence of electrical resistivity exhibits semiconducting behavior at x =0, a metal-semiconductor transition for 0.08≤ x ≤0.29, and metallic behavior down to 4.2 K for x ≥0.39.…
An effective low-energy Hamiltonian of interacting electrons in conducting single-wall carbon nanotubes with arbitrary chirality is derived from the microscopic lattice model. The parameters of the Hamiltonian show very weak dependence on the chiral angle, which makes the low-energy properties of conducting chiral nan…
Substitution of Ni for Mn in La0.67Sr0.33MnO3 (LSMO) lowers the Curie temperature TC from 365 K for LSMO to 194 K for La0.67Sr0.33(Mn0.8Ni0.2)O3, which exhibits a cluster glass-like state. The oxide is insulating under both zero field and 60 kOe, but application of the magnetic field induces colossal magnetoresistance…
ADVERTISEMENT RETURN TO ISSUEPREVCommunication to the...Communication to the EditorNEXTSynthesis of Polymethylene Block Copolymers by the Polyhomologation of OrganoboranesKenneth J. Shea, Chad L. Staiger, and Sun Y. LeeView Author Information Department of Chemistry, University of California, Irvine, Irvine, Californi…
The local structure of erbium-doped silicon produced by the laser ablation technique is investigated by Er LIII-edge x-ray absorption fine structure analysis. The combined analysis of extended x-ray absorption fine structure analysis and an x-ray absorption near-edge structure simulation based on multiple-scattering t…