Showing papers in "Solid State Communications in 1987"

TL;DR: In this paper, the self-diffusion of the radioisotope 67Cu in nanocrystalline copper has been measured by serial sectioning with the aid of ion-beam sputtering.

TL;DR: In this article, the magnetic susceptibility of the emeraldine form of polyaniline was studied and a model based upon the transition upon protonation from isolated doubly charged protonated diimine groups to a polaronic metal was suggested, together with the role of polarons at the surface of and within the disordered small metal particles formed.

TL;DR: In this article, the structural and electrical properties of new radical anion salts of dicyanoquinodiimine derivatives have been investigated (R1,R2-DCNQI)2M (R 1,R 2-CH3,Cl, MCu).

TL;DR: In this article, a detailed high temperature X-ray diffraction was performed to study the structural phase of YBa 2 Cu 3 O 7−δ, and the results indicated the existence of a reversible orthorhombic to tetragonal phase transition at a temperature close to 750°C.

TL;DR: In this paper, the copper L2,3 soft x-ray absorption spectra of the single phase high temperature superconductor YBa2Cu3O≈7 have been measured by using synchrotron radiation at LURE.

TL;DR: In this article, a positive correlation is found between the volume fration of the orthorhombic phase and the superconducting transition temperature, and it is shown that the order-disorder transition associated with the structural vacancies is reversible, provided there has been no oxygen loss.

TL;DR: In this paper, the superconductivity of R-Ba-Cu-O compounds for rare earths R = Sm through Ho was investigated and an approximate value for the upper critical field slope of the Gd compound was given.

TL;DR: In this article, it was shown by means of electron microscopy and electron diffraction that the structural vacancies in Ba 2 YCu 3 O 7−δ undergo an order-disorder transformation accompanied by a change in symmetry from orthorhombic to tetragonal.

TL;DR: The phase transition temperature of barium titanate ceramics was measured in changing the grain sizes for grain diameters ⪅20 μm and dielectric property remarkably changes.

TL;DR: In the inhomogeneous structure, which is the contact of two semiconductors with mutually inverted bands, two-dimensional non-degenerate electron states exist as discussed by the authors, and these states appear due to the supersymmetry of an effective Hamiltonian and do not depend on the specific form of the transition region.

TL;DR: In this paper, the authors investigated differential inelastic scattering cross sections for low energy electrons in noble and transition metals on the basis of dielectric response theory, and showed that A(T) is a good approximation to λ(E)K(E, T) in the description of many physical systems.

TL;DR: In this paper, the series of rare-earth (R)-barium copper oxides with nominal composition (RBa2)Cu3O9−σ and the prototype compound (YBa2)cu3O 9−σ have been prepared from the R (except Pm), Y, and Cu oxides and Ba carbonate by sintering, followed by arc-melting and annealing in pure oxygen.

TL;DR: In this paper, the electron mobility of δ-doped GaAs grown by molecular-beam epitaxy is determined for two-dimensional doping concentrations ranging from 10 10 cm −2 to 10 13 cm−2.

TL;DR: In this article, hole transport data in polymethylphenylsilylene (PMPS) has been analyzed in both a modified Arrhenius framework and in terms of a picture of hopping in a Gaussian distribution of states broadened by disorder.

TL;DR: In this paper, the magnetic susceptibility of La2−xSrxCuO4 for x = 0, 0.10, 0., 0.15, and 0.20 was investigated.

TL;DR: In this article, a Coulomb interaction Ucd∼9 eV between the 2p 3 2 core hole and the localized 3d valence electron has been estimated, which is consistent with the formation of holes L in the oxygen derived band, i.e. of the 3d9 L configuration, with additional oxygen x in YBa2Cu3O6.5+x, which should play a key role in the high-Tc superconductivity.

TL;DR: In this article, a low-energy electron diffraction intensity analysis of the c(2 × 2) structure formed by 1 2 monolayer of Au on a clean Cu {0 0 1} surface reveals a single mixed-layer structure which can be properly called an ordered surface alloy.

TL;DR: The Electron Paramagnetic Resonance (EPR) of Mn 4+ in the rhombohedral low temperature phase of BaTiO 3 has been observed at 19.3 and 13.0 GHz as discussed by the authors.

TL;DR: On the basis of photoemission results on La 2- x Sr x CuO 4- y and YBa 2 Cu 3 O y, it is suggested that carriers doped in the otherwise insulating samples are oxygen p holes rather than Cu d holes as mentioned in this paper.

TL;DR: In this paper, the IR and Raman spectra of superconducting MBa2Cu3O7 (M = Y, Sm, Eu, Gd, Ho) have been measured at several temperatures between 4 and 300 K.

TL;DR: In this article, it was shown that when Ba 2 YCu 3 O 7 is heated above room temperature, it progressively loses all oxygen from the O4 sites on the b-axis chains, while the remaining oxygen sites remain fully occupied.

TL;DR: In this paper, an electron microscope fitted with a magnetic prism spectrometer and a parallel recording system based on a SIT (silicon intensified target) detector has been used to measure the electron energy-loss spectrum of TiO2.

TL;DR: In this article, a model taking account of strong interactions between the HOMO and totally symmetric intramolecular vibration modes in the TTF-analog molecules is solved to give the superconducting transition temperature Tc, which proves to be able to become 8 K with reasonable parameter values for the β-(BEDT-TTF)I3 superconductors.

TL;DR: In this article, the multilayer relaxation of clean Fe{001} and 3-layer Ni films was determined by low-energy electron diffraction (LEED) and Auger electron spectroscopy.

TL;DR: The high-temperature superconductor YBa 2 Cu 3 O 7-x has been characterized by thermogravimetry in the 600-1100 K range under oxygen pressures from 10 -3 to 1 atm.

TL;DR: In this paper, NMR data for 89Y in the high Tc superconductor YBa2Cu3O9-δ (δ ≈ 2.1) in both the normal and mixed states are presented.

TL;DR: In this paper, the authors present the results of tight-binding band structure calculations performed in the framework of the adiabatic Su-Schrieffer-Heeger Hamiltonian.

TL;DR: In this paper, the photoluminescences observed in undoped poly(thiophene) and poly(3-methylthiophenes) films decrease in the intensity with a slight blue shift by electrochemical C1O-4 doping.

TL;DR: Two-dimensional imaging of the nucleation and the dynamics of current filaments generated in homogeneous p-doped germanium at 4.2 K during impurity impact ionization induced avalanche breakdown has been performed.