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FePt/B4C multilayer thin films were deposited using magnetron sputtering with different boron carbide layer thicknesses. Experimental results suggest that the B4C layers effectively serve as spacers to separate the FePt layers, making the multilayer configuration stable even after film annealing at elevated temperatures. On the other hand, B and C are found to incorporate into the FePt layer, which is responsible for the FePt grain growth confinement and grain separation, and eventually affects the magnetic properties of the composite film. [ABSTRACT FROM AUTHOR]

Using combined microscopy and optical characterizations, the authors demonstrate effective Er doping into freestanding ZnO nanowires via ion implantation. The Er atoms are observed to take the substitutional sites in ZnO without causing obvious distortion to the host lattice. While the band gap threshold of the Er doped ZnO nanowires remains similar to that of the undoped ZnO, band tail states are created in the band structure of the ZnO upon Er doping. Room temperature 1.54 μm emission is achieved in the doped nanowire sample after oxygen annealing. In particular, the generation of the band tail state(s) in the band gap of the ZnO nanowire host is found to be responsible for the 1.54 μm emission under the below-band-gap indirect excitation. [ABSTRACT FROM AUTHOR]

We report on a high-power diode–end–pumped polycrystalline Yb:Y2O3 ceramic laser. Under the pump power of 27 W, continuous-wave output power of 9.2 W at 1078 nm has been obtained by using an output coupler of R=96%. The laser had a threshold of 3.1 W and a slope efficiency of 41%. Comparative studies on the laser performance between the Yb:Y2O3 ceramic and the Yb:yttrium aluminum garnet (YAG) single crystal show that at the same doping concentration of 8 at. %, higher laser efficiency can be obtained in the Yb:Y2O3 ceramic laser than in the Yb:YAG single crystal laser. [ABSTRACT FROM AUTHOR]

The technique of point-defect engineering (PDE), with excess vacancies produced near the surface region by MeV Si ion implantation, has been applied to form ultrashallow junctions with sub-keV B implants. PDE can reduce boride-enhanced diffusion that dominates the enhanced diffusion of ultralow energy B implants. PDE can further sharpen the dopant profile and enhance boron activation. For 1×1015/cm2, 0.5 keV B implant, B solid solubility has been enhanced over a wide temperature range of 750–1000 °C, with an enhancement factor of 2.5 at 900 °C. These features have enabled a shallower and sharper box-like boron junction achievable by PDE in combination with ultralow energy 0.5 keV B implantation. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We report on a diode-pumped polycrystalline Yb:Y[SUB2]O[SUB3] ceramic laser. We demonstrate that, with a pump power of 11 W at 937 nm, 0.75-W cw laser output at 1078 nm can be obtained from the laser. The laser had a threshold of 4.7 W and a slope efficiency of 12.6% when an output coupler of R = 98% was used. [ABSTRACT FROM AUTHOR]

Using infrared spectroscopic ellipsometry, the optical constants of LaNiO[sub 3] thin films on Pt(111)-Ti-SiO[sub 2]-Si substrates are obtained in the 2.5-12.6 μm range, in which the infrared optical constants decrease when the annealing temperature increases from 600 to 650 °C. At the same time, the infrared optical properties of PbZr[sub χ]Ti[sub 1-χ]O[sub 3](PZT) thin films with χ=0.3 and 0.5 on LaNiO[sub 3]-Pt-Ti-SiO[sub 2]-Si substrates are simultaneously studied with respect to annealing temperatures. The infrared optical properties are associated closely with the grain size and crystallographic orientation of the films induced by annealing temperature, combined by the particular substrate. For the Ni-PZT-LaNiO[sub 3]-Pt multilayer heterostructures, the infrared absorptance better than 99% can be achieved for PZT pyroelectric thin film infrared microsensors. © 2001 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We report the first bipolar Monte Carlo calculations of steady-state minority-electron transport in room-temperature p-GaAs including multiband electron-hole scattering with and without hole overlap factors. Our results show how such processes, which make a significant contribution to the minority-electron energy loss rate, can affect steady-state minority-electron transport. Furthermore, we discuss several other issues which we believe should be investigated before present Monte Carlo treatments of electron-hole scattering can provide quantitative information. [ABSTRACT FROM AUTHOR]