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Quantum-coupled single-electron thermal to electric conversion scheme
D. M. Wu, P. L. Hagelstein, P. Chen, K. P. Sinha, and A. Meulenberg
JAThermal to electric energy conversion with thermophotovoltaics relies on radiation emitted by a hot body, which limits the power per unit area to that of a blackbody. Microgap thermophotovoltaics take advantage of evanescent waves to obtain higher throughput, with the power per unit area limited by the internal blackbody, which is n2 higher. We propose that even higher power per unit area can be achieved by taking advantage of thermal fluctuations in the near-surface electric fields.
Characterization of a CO2/N2/Ar supersonic flowing discharge
D. J. Drake, S. Popović, and L. Vušković
In all aspects besides the flow speed and gas temperature, the conditions we study correspond to Martian entry plasma. Plasma parameters were determined by optical emission spectroscopy techniques. A kinetic model for the discharge was developed to calculate the electron density and compare with experimental data.
Multistep damage evolution process in cubic zirconia irradiated with MeV ions
S. Moll, L. Thomé, G. Sattonnay, A. Debelle, F. Garrido, L. Vincent, and J. Jagielski
A combination of Rutherford backscattering spectrometry and channeling, x-ray diffraction, and transmission electron microscopy experiments was used to study the damage formation in cubic yttria-stabilized zirconia single crystals irradiated with medium-energy (4 MeV) heavy (Au) ions. The damage buildup, which is accounted for in the framework of the multistep damage accumulation model, occurs in three steps.
X-ray ablation of hyaluronan hydrogels: Fabrication of three-dimensional microchannel networks
B. M. Weon, S. Chang, J. Yeom, S. K. Hahn, J. H. Je, Y. Hwu, and G. Margaritondo
We present a simple and highly versatile protocol for polymer ablation: hard x-ray irradiation makes it possible to rapidly depolymerize hyaluronan hydrogels and fabricate three-dimensional network of microchannels.
Flexible active-matrix cells with selectively poled bifunctional polymer-ceramic nanocomposite for pressure and temperature sensing skin
Ingrid Graz, Markus Krause, Simona Bauer-Gogonea, Siegfried Bauer, Stephanie P. Lacour, Bernd Ploss, Martin Zirkl, Barbara Stadlober, and Sigurd Wagner
Our bifunctional frontplane element is based on a composite foil of piezoelectric ceramic lead titanate nanoparticles embedded in a ferroelectric poly(vinylidene fluoride trifluoroethylene) polymer matrix. Bifunctionality to pressure and temperature changes is achieved by a sequential, area selective two-step poling process, where the polarization directions in the nanoparticles and the ferroelectric polymer are adjusted independently.
Sticking properties of an in situ prepared polymer film
David Pires, Jean-Baptiste Fleury, and Yves Galerne
Colloidal silica particles of micrometric size are dispersed in a nonionic nematic liquid crystal and are glued on a glass-indium-tin-oxide substrate by means of an in situ synthesized acrylate polymer film. We show that the gluing properties of the film depend on whether the polymerization of the film is initiated via volume or surface nucleation, and whether the film is synthesized before or after the beads are deposited on the substrate. Typically, the adhesion is measured around 25 pN which nevertheless could be interesting for particular applications.
J. Appl. Phys. 106, 034904 (2009)
Diffractive imaging using a polychromatic high-harmonic generation soft-x-ray source
Ruben A. Dilanian, Bo Chen, Garth J. Williams, Harry M. Quiney, Keith A. Nugent, Sven Teichmann, Peter Hannaford, Lap V. Dao, and Andrew G. Peele
A new approach to diffractive imaging using polychromatic diffraction data is described. The method is tested using simulated and experimental data and is shown to yield high-quality reconstructions.
J. Appl. Phys. 106, 023110 (2009)
Optoacoustic method for determination of submicron metal coating properties: Theoretical consideration
Ivan M. Pelivanov, Daria S. Kopylova, Natalia B. Podymova, and Alexander A. Karabutov
Presented is a theoretical consideration of the optoacoustic conversion in a system consisting of a metal film deposited on a transparent dielectric substrate and covered by a transparent liquid. A method for nondestructive evaluation of submicron metal coatings properties is proposed.
Energy transfer in nanowire solar cells with photon-harvesting shells
C. H. Peters, A. R. Guichard, A. C. Hryciw, M. L. Brongersma, and M. D. McGehee
Organic molecules that absorb strongly in the near infrared, where silicon absorbs weakly, are bonded to the surface of silicon nanowires (SiNWs) forming a thin shell. An array of 7-µm-long nanowires with a diameter of 50 nm is able to absorb over 85% of the photons above the bandgap of silicon. We measure a 60% increase in photocurrent from a planar silicon-on-insulator.
Efficiency limits of Si/SiO2 quantum well solar cells from first-principles calculations
Thomas Kirchartz, Kaori Seino, Jan-Martin Wagner, Uwe Rau, and Friedhelm Bechstedt
Efficiency limits are calculated for ideal systems according to the Shockley–Queisser theory but also for more realistic devices with finite mobilities, nonradiative lifetimes, and absorption coefficients. Thereby, we identify the critical values for mobility and lifetime that are required for efficient single junction as well as tandem solar cells.
Feasibility study of high-resolution coherent diffraction microscopy using synchrotron x-rays focused by Kirkpatrick–Baez mirrors
Yukio Takahashi, Yoshinori Nishino, Hidekazu Mimura, Ryosuke Tsutsumi, Hideto Kubo, Tetsuya Ishikawa, and Kazuto Yamauchi
High-flux coherent x-rays are necessary for the improvement of the spatial resolution in coherent x-ray diffraction microscopy (CXDM). High-resolution CXDM using Kirkpatrick–Baez (KB) mirrors is proposed, and the mirrors are designed for experiments using the transmission scheme at SPring-8.
Optimizing the morphology of metal multilayer films for indium tin oxide (ITO)-free inverted organic solar cells
Scanning electron microscopy, atomic force microscopy, and optical spectroscopy are used to illustrate how ultrathin Al interlayers influence the morphology of Ag layers evaporated on top of organic materials and how closed layers with good conductivity can be achieved. Multilayer metal contacts are used to fabricate top-illuminated small-molecule organic solar cells (SM-OSCs) which reach efficiencies comparable to conventional SM-OSCs that employ tin-doped indium oxide as electrode. It is shown that combinations of Al and Au lead to similar results, suggesting a similar mechanism for the influence on morphological development of both Ag and Au.
