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In the secondary ion mass spectrometry (SIMS), use of cluster ions has an advantage of producing a high sensitivity of intact large molecular ions over monatomic ions. This paper presents further yield enhancement of the intact biomolecular ions by measuring the secondary ions emitted in the forward direction. Phenylalanine amino acid films deposited on self-supporting thin Si3N4 films were bombarded with 5MeV C60 ions. Secondary ions emitted in the forward and backward directions were measured. The yield of intact phenylalanine molecular ions emitted in the forward direction is significantly enhanced compared to the backward direction while fragment ions are suppressed. This suggests a large potential of using transmission cluster ion SIMS for the analysis of biological materials. [ABSTRACT FROM AUTHOR]

The thermophysical ratio of constant pressure heat capacity to hemispherical total emissivity cP(T)/εT(T) of liquid Mo (Tm=2895 K) was analytically estimated from the radiative cooling curve measured during containerless melting and solidification via electrostatic levitation. cP(T) and εT(T) were then derived to describe the temperature-dependent cooling behavior of liquid Mo before nucleation. Spherical Mo liquids by surface tension kept their spherical shapes during containerless solidification becoming single crystals confirmed by the truncated octahedron bound by eight {111} planes exposed by preferential macroetching and the spotty Laue patterns by backreflection. [ABSTRACT FROM AUTHOR]

We have, for the first time, made quasi-particle tunneling measurements on a YBa2Cu3O7-x(001)/Y2O3 (001)/YBa2 Cu3 O7-x (001)junction, which was epitaxially grown on a MgO(100) substrate in an in-situ process. Both layers of YBa2 Cu3 O7-x showed the same superconducting transition of Tc end =86 K with ΔT(R=10–90%)=1.5 K. Quasi-particle tunneling in the direction perpendicular to the Cu-O planes was measured. A gap parameter Δ(4.5 K) of 9.0±0.2 meV and a value of 2Δ/kTc of 3.5+0.4-0.6 were obtained. [ABSTRACT FROM AUTHOR]

Superconducting Nd-Ce-Cu-O thin films were epitaxially grown on SrTiO3 (100) by activated reactive evaporation. As-grown films showed the metallic temperature dependence of the resistivity and superconducting transition at 12.5 K (R=0). The remarkable parallel shift of the onset temperature of the resistive transition in the magnetic fields was observed. Ginzburg–Landau coherence lengths along the c axis and in the basal plane are 7 and 96 Å, respectively. [ABSTRACT FROM AUTHOR]

Ferroelectric BaTiO3 thin films were directly and epitaxially grown on SrTiO3 single crystal and epitaxial Pt film substrates by activated reactive evaporation. The substrate temperature was around 600 °C. For (100) oriented as-grown films, a typical ferroelectric hysteresis loop and a maximum of dielectric constant at about 115 °C were observed. The resistivity was as high as 109 Ω cm and the breakdown voltage was 2.7 MV/cm for as-grown BaTiO3 films. [ABSTRACT FROM AUTHOR]

Normal-metal/insulator/superconductor (NIS) junctions were fabricated using thin films of YBa2Cu3O7-x (YBCO) or ErBa2Cu3O7-x. These were epitaxially grown on single-crystal SrTiO3 by the activated reactive evaporation method. For some NIS junctions prepared on SrTiO3 (110) substrates, we observed multipeaks in the differential conductance versus voltage curve. NIS junctions using single-crystal YBCO films on SrTiO3 (100) showed a set of peaks, from which we obtained a gap parameter of 11.5±1.5 meV at 4.4 K and a coupling constant of 3.2±0.4. [ABSTRACT FROM AUTHOR]

The orientation of YBa2Cu3O7-x thin films grown on (110) planes of SrTiO3 by activated reactive evaporation was investigated by means of reflection high-energy electron diffraction. The orientation of the films depended on the substrate temperature. The films with (110) planes parallel to the substrate surface grew in a narrow range of substrate temperatures around 530 °C, while the films with (103) planes parallel to the surface grew at temperatures above 600 °C. The change of the epitaxial orientation with the substrate temperature is discussed in terms of the temperature dependence of the lattice mismatch between YBa2Cu3O7-x and SrTiO3. [ABSTRACT FROM AUTHOR]