Now showing items 21-40 of 112

    • Structural and optical characterization of infrared hot electron transistor 

      Jung, Hyeson; Pinsukanjana, Paul; Dutta, Mitra; Choi, Kwong-Kit; Tidrow, Meimei Z. (American Institute of Physics, 2010-08-01)
      We present structural, optical, and transport characterization of long wave infrared hot electron transistor (IHET) based on doped quantum wells of InGaAs/AlGaAs. The atomic resolution images and x-ray diffraction patterns ...
    • Configuration of membrane-bound proteins by x-ray reflectivity 

      Chen, Chiu-Hao; Ma´lkova, Sa´rka; Cho, Wonhwa; Schlossman, Mark L. (American Institute of Physics, 2010-11)
      In this presentation we review our recent work using x-ray reflectivity to determine the configuration of membrane-bound proteins. The reflectivity data is analyzed in terms of the known crystallographic structure of ...
    • Semianalytic model of electron pulse propagation: Magnetic lenses and rf pulse compression cavities 

      Berger, Joel A.; Schroeder, W. A. (American Institute of Physics, 2010-12-15)
      The analytical Gaussian electron pulse propagation model of Michalik and Sipe [J. Appl. Phys. 99, 054908 (2006)] is extended to include the action of external forces on the pulse. The resultant ability to simulate efficiently ...
    • Higher Order Painlevé Equations and their Symmetries via Reductions of a Class of Integrable Models 

      Aratyn, H.; Gomes, J.F.; Zimerman, A.H. (Institute of Physics, 2011-06-10)
      Higher order Painlevé equations and their symmetry transformations belonging to extended affine Weyl groups An(1) are obtained through a self-similarity limit of a class of pseudo-differential Lax hierarchies with symmetry ...
    • Photoluminescence and Raman spectroscopy of polycrystalline ZnO nanofibers deposited by electrospinning 

      Sen, Banani; Stroscio, Michael; Dutta, Mitra (Springer Verlag, 2011-06-15)
      The technique of electrospinning offers the advantage of growing nanowires in bulk quantities in comparison with traditional methods. We report optical studies of polycrystalline zinc oxide (ZnO) nanofibers (∼100 nm thick ...
    • Sign of Kurtosis near the QCD Critical Point 

      Stephanov, M. A. (American Physical Society, 2011-07)
      We point out that the quartic cumulant (and kurtosis) of the order parameter fluctuations is universally negative when the critical point is approached on the crossover side of the phase separation line. As a consequence, ...
    • CdZnTe Radiation Detectors with HgTe/HgCdTe Superlattice Contacts for Leakage Current Reduction 

      Chang, Y.; Grein, C.H.; Becker, C.R.; Wang, X.J.; Duan, Q.; Ghosh, S.; Dreiske, P.; Bommena, R.; Zhao, J.; Carmody, M.; Aqariden, F.; Sivananthan, S. (Institute of Electrical and Electronics Engineers, 2011-08)
      CdZnTe-based heterojunctionp-i-n or M-π-n detectors using HgTe/CdTe superlattice contacts are modeled and designed to reduce leakage currents under high electric fields and thereby improve X-ray and γ-ray detector performance. ...
    • Fabrication and characterization of SmO0.7F0.2FeAs bulk with a transition temperature of 56.5 K 

      Liu, Zhiyong; Ma, Lin; Zhao, Junjing; Yan, Binjie; Suo, Hongli (Springer Verlag, 2011-10)
      The superconductivity of iron-based superconductor SmO0.7F0.2FeAs was investigated. The SmO0.7F0.2FeAs sample was prepared by the two-step solid-state reaction method. The onset resistivity transition temperature is as ...
    • Temperature dependent photoluminescence from porous silicon nanostructures: Quantum confinement and oxide related transitions 

      Ray, Mallar; Bandyopadhyay, Nil Ratan; Ghanta, Ujjwal; Klie, Robert F.; Pramanick, Ashit Kumar (American Institute of Physics, 2011-11)
      Temperature dependent photoluminescence (PL) spectroscopy along with structural investigations of luminescent porous Si enable us to experimentally distinguish between the relative contributions of band-to-band and oxide ...
    • X-ray fluorescence from a model liquid/liquid solvent extraction system 

      Bu, Wei; Hou, Binyang; Mihaylov, Miroslav; Kuzmenko, Ivan; Lin, Binhua; Meron, Mati; Soderholm, L.; Luo, Guangming; Schlossman, Mark L. (American Institute of Physics, 2011-11-15)
      X-ray fluorescence near total reflection (XFNTR) is measured from the liquid/liquid interface between dodecane and an ErCl3 aqueous solution by monitoring L shell Er emission lines. A custom sample cell is used to minimize ...
    • Dark side of the Higgs boson 

      Low, Ian; Schwaller, Pedro; Shaughnessy, Gabe; Wagner, Carlos E. M. (American Physical Society, 2012-01)
      Current limits from the Large Hadron Collider exclude a standard model-like Higgs mass above 150 GeV, by placing an upper bound on the Higgs production rate. We emphasize that, alternatively, the limit could be interpreted ...
    • Charge transport in two different conductive polymer and semiconducting quantum dot nanocomposite systems 

      Biswas, Sushmita; Li, Yang; Stroscio, Michael A.; Dutta, Mitra (American Institute of Physics, 2012-02)
      Charge transport mechanisms have been investigated in two different nanocomposite structures made of conductive polymers embedded with II-VI semiconducting quantum dots. Photoluminescence data indicated charge transport ...
    • Constraint on Parity-Violating Muonic Forces 

      Barger, Vernon; Chiang, Cheng-Wei; Keung, Wai-Yee; Marfatia, Danny (American Physical Society, 2012-02)
      Using the nonobservance of missing mass events in the leptonic kaon decay K ! X, we place a strong constraint on exotic parity-violating gauge interactions of the right-handed muon. By way of illustration, we apply it ...
    • The Little Skyrmion: New Dark Matter for Little Higgs Models 

      Gillioz, Marc; Manteuffel, Andreas von; Schwaller, Pedro; Wyler, Daniel (Springer Verlag, 2012-03)
      We study skyrmions in the littlest Higgs model and discuss their possible role as dark matter candidates. Stable massive skyrmions can exist in the littlest Higgs model also in absence of an exact parity symmetry, since ...
    • First-principles study of the atomic and electronic structures of misfit-layered calcium cobaltite (Ca2CoO3)(CoO2)1.62 using rational approximants 

      Klie, Robert; Zapol, Peter; Öğüt, Serdar; Rébola, Alejandro (American Physical Society, 2012-04)
      The atomic and electronic structures of the misfit-layered thermoelectric oxide material Ca3Co4O9 are investigated using detailed first-principles computations performed within the framework of density functional theory ...
    • Observations of Co4+ in a higher spin state and the increase in the Seebeck coefficient of thermoelectric Ca3Co4O9 

      Klie, R. F.; Qiao, Q.; Paulauskas, T.; Gulec, A.; Rebola, A.; Prange, M. P.; Idrobo, J. C.; Pantelides, S. T.; Kolesnik, S.; Dabrowski, B.; Ozdemir, M.; Boyraz, C.; Mazumdar, D.; Gupta, A.; Öğüt, S. (American Physical Society, 2012-05)
      Ca3Co4O9 has a unique structure that leads to exceptionally high thermoelectric transport. Here we report the achievement of a 27% increase in the room-temperature in-plane Seebeck coefficient of Ca3Co4O9 thin films. We ...
    • Relativistic theory of hydrodynamic fluctuations with applications to heavy-ion collisions 

      Kapusta, J. I.; Muller, B.; Stephanov, M. (American Physical Society, 2012-05)
      We develop the relativistic theory of hydrodynamic fluctuations for application to high-energy heavy-ion collisions. In particular, we investigate their effect on the expanding boost-invariant (Bjorken) solution of ...
    • Current eigenmodes and dephasing in nanoscopic quantum networks 

      Can, Tankut; Dai, Hui; Morr, Dirk K. (American Physical Society, 2012-05)
      Using the nonequilibrium Keldysh Green’s function formalism, we show that the nonequilibrium charge transport in nanoscopic quantum networks takes place via current eigenmodes that possess characteristic spatial patterns.We ...
    • Doping dependence of the specific heat of single-crystal BaFe2(As1-xPx)2 

      Chaparro, C.; Fang, L.; Claus, H.; Rydh, A.; Crabtree, G. W.; Stanev, V.; Kwok, W. K.; Welp, U. (American Physical Society, 2012-05)
      We present specific heat measurements on a series of BaFe2(As1-xPx )2 single crystals with phosphorous doping ranging from x = 0.3 to x = 0.55. Our results reveal that BaFe2(As1-xPx )2 follows the scaling C/Tc ≈ T ...
    • Total Width of 125 GeV Higgs Boson 

      Barger, Vernon; Ishida, Muneyuki; Keung, Wai-Yee (American Physical Society, 2012-06)
      By using the LHC and Tevatron measurements of the cross sections to various decay channels relative to the standard model Higgs boson, the total width of the putative 125 GeV Higgs boson is determined as 6:1þ7:7 2:9 ...