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Excitation-current-density and temperature-dependent cathodoluminescence (CL) spectra were measured for rocksalt-structured MgxZn1-xO films with x = 0.92–0.61. A deep UV luminescence (DUVL) band was predominantly observed in an energy range of 4.91–5.86 eV for all the films at 6–300 K. The analysis based on a rate equation model confirms that the DUVL band is attributed to the near-band-edge emission. Temperature-dependent CL spectra were quantified in terms of peak energy shifts and full width at half maximum values. Relatively high equivalent internal quantum efficiencies of 2.5%–11% were obtained for the RS-MgxZn1-xO films. [ABSTRACT FROM AUTHOR]

We investigated the effect of Sn doping on the optical, electrical, and magneto transport properties of epitaxial α-Ga2O3 thin films grown by mist-Chemical Vapour Deposition. Sn introduces a shallow donor level at ∼0.1 eV and has a high solubility allowing doping up to 1020cm-3. The lowest obtained resistivity of the films is 2.0×10-1Ω cm. The Sn doped films with a direct band gap of 5.1 eV remain transparent in the visible and UV range. The electrical conduction mechanism and magneto-transport have been investigated for carrier concentrations below and above the insulatormetal transition. The magnetic properties of the neutral Sn donor and the conduction electrons have been studied by electron spin resonance spectroscopy. A spin S=1/2 state and C3V point symmetry of the neutral Sn donor is found to be in good agreement with the model of a simple SnGa center. [ABSTRACT FROM AUTHOR]

BaZrO3 doped GdBa2Cu3O7-δ superconductor was prepared by pulsed layer deposition using a KrF excimer laser, which showed isotropic characteristics of critical current density, JC, for magnetic-field orientations, ∼4.0×109 A m-2 at 1.0 T. Microstructural and morphological characterization of resulting artificial pinning centers were conducted by transmission electron microscopy and electron tomography, which confirmed the presence of one-dimensional artificial pinning centers, BaZrO3 nanorods. Since there is noticeable anisotropy from GdBa2Cu3O7-δ superconductor without doping BaZrO3, the pinning observed for all magnetic-field orientations are due to the high density and high dispersion of these BaZrO3 nanorods with very wide angular distributions. [ABSTRACT FROM AUTHOR]

BaZrO3 doped GdBa2Cu3O7-δ superconductor was prepared by pulsed layer deposition using a KrF excimer laser, which showed isotropic characteristics of critical current density, JC, for magnetic-field orientations, ∼4.0×109 A m-2 at 1.0 T. Microstructural and morphological characterization of resulting artificial pinning centers were conducted by transmission electron microscopy and electron tomography, which confirmed the presence of one-dimensional artificial pinning centers, BaZrO3 nanorods. Since there is noticeable anisotropy from GdBa2Cu3O7-δ superconductor without doping BaZrO3, the pinning observed for all magnetic-field orientations are due to the high density and high dispersion of these BaZrO3 nanorods with very wide angular distributions. [ABSTRACT FROM AUTHOR]

Structures of interfaces between AlN and MgB2 thin films were investigated by cross-sectional transmission electron microscopy. These layers were deposited on sapphire substrate with different orientations by a conventional method. A thick amorphous layer was present between films in the case of r-plane substrate, whereas many AlN crystals were grown epitaxially in the case of c-plane substrate. Then NbN/AlN/MgB2 trilayers were intentionally fabricated on sapphire c-plane and showed Josephson and quasiparticle tunneling property with small subgap leakage current. [ABSTRACT FROM AUTHOR]

The transmission electron microscopy approach is employed to explain the preparation and the properties of the BaZr[O.sub.3] doped Gd[Ba.sub.2][Cu.sub.3][O.sub.7-[delta]] superconductor. The pinning centers of the doping element is shown to lead to the generation of isotropic superconductivity in the superconductors.

Presents a study which reported the electrical properties of selenium- and zinc-doped Ga[sub0.5]In[sub0.5]P and (A[sub0.5]Ga[sub0.5][sub0.5]In[sub0.5]P grown by atmospheric pressure metalorganic chemical vapor deposition. Materials and methods used; Effect of the buffer layer on the Hall measurement; Details on the doping of selenium and zinc.

Presents a study which investigated the characteristics of terbium-iron-cobalt (Tb-Fe-Co) amorphous films in order to optimize compositions suitable for magneto-optical recording medium with high readout signal. Measurement of the crystallization temperature; Evaluation of Tb-Fe-Co films as a magneto-optical recording medium; Discussion on how the magnetic properties of films affect the dynamic writing and erasing characteristics in magneto-optical recording.

Presents information on a study which developed a connection rule of wave functions at a heterointerface. Physics of heterointerfaces; Estimation of band discontinuity between GaAs and AlGaAs quantum wells.

Examines the current-voltage characteristics of gallium arsenide/aluminum[subx] gallium[sub1-x] arsenic/gallium heterobarriers grown by metalorganic chemical vapor deposition. Calculation of the current; Description of the tunneling effective mass; Mechanism which plays an important role in electron tunneling in the aluminum gallium arsenide barrier.

The supercritical gas absorption isotherms are classified into Henry-type isotherms, virial isotherms and cooperative isotherms based on an increase in fluid-fluid interaction. This classification is associated with the equation of state (EOS) for a confined fluid in the interaction potential fields of micropores.

Examines the nonequilibrium electron transport in an AlGaAs/gallium arsenide (GaAs) double-heterojunction bipolar transistor (DHBT). Fabrication of the DHBT; Band diagram of an AlGaAs/GaAs DHBT; Base characteristics of the DHBT.

Provides information on a study which investigated electron transfer into gallium arsenide in the dependence of transfer ratio of a hot-electron transistor. Methods; Results; Discussion.