Now showing items 233-252 of 376

    • On the accuracy limits of orbital expansion methods: Explicit effects of k-functions on atomic and molecular energies 

      Valeev, Edward F.; Allen, Wesley D.; Hernandez, Rigoberto; Sherrill, C. David; Schaefer, Henry F. (Georgia Institute of TechnologyAmerican Institute of Physics, 2003-05)
      For selected first- and second-row atoms, correlation-optimized Gaussian k functions have been determined and used in the construction of septuple-ζ basis sets for the correlation-consistent cc-pVXZ and aug-cc-pVXZ series. ...
    • On the polarization of the green emission of polyfluorenes 

      Yang, X. H.; Neher, D.; Spitz, C.; Zojer, Egbert; Brédas, Jean-Luc; Guntner, R.; Scherf, U (Georgia Institute of TechnologyAmerican Institute of Physics, 2003-10)
      An experimental and theoretical study of the anisotropic optical properties of polyfluorenes (PFs) bearing ketonic defects is presented. Polarized emission experiments performed on photooxidized aligned PF layers indicate ...
    • Ontology of temperature in nonequilibrium systems 

      Popov, Alexander V.; Hernandez, Rigoberto (Georgia Institute of TechnologyAmerican Institute of Physics, 2007-06)
      The laws of thermodynamics provide a clear concept of the temperature for an equilibrium system in the continuum limit. Meanwhile, the equipartition theorem allows one to make a connection between the ensemble average of ...
    • Optical and electrical interconnect partition length based on chip-to-chip bandwidth maximization 

      Naeemi, Azad; Xu, Jianping; Mule’, Anthony V.; Gaylord, Thomas K.; Meindl, James D. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, 2004-04)
      The lengths beyond which board-level optical waveguides are capable of transferring a larger number of bits per second than electrical interconnects are found for various technology generations. As technology scales ...
    • Optical correlation using gated localized holography 

      Karbaschi, Arash; Momtahan, Omid; Adibi, Ali; Javidi, Bahram (Georgia Institute of TechnologySociety of Photo-optical Instrumentation Engineers (SPIE), 2005-08)
      We present a new technique for optical correlation using gated holographic recording by which the holograms are localized in separate slices along the recording medium. We compare the performance of localized holographic ...
    • Optical properties of singly charged conjugated oligomers: A coupled-cluster equation of motion study 

      Ye, A.; Shuai, Zhigang; Kwon, O.; Brédas, Jean-Luc; Beljonne, David (Georgia Institute of TechnologyAmerican Institute of Physics, 2004-09)
      We have implemented a coupled-cluster equation of motion approach combined with the intermediate neglect of differential overlap parametrization and applied it to study the excited states and optical absorptions in positively ...
    • Optical single-angle plane-wave transmittances/reflectances from Schwarzschild objective variable-angle measurements 

      Gaylord, Thomas K.; Kilby, Gregory R. (Georgia Institute of TechnologyAmerican Institute of Physics, 2004-02)
      Photonic crystal structures and other nanoscale and microscale optical structures are centrally important to future device technology. The fundamental infrared single-angle plane-wave experimental characterization of these ...
    • Optical transmission of polymer pillars for chip I/O optical interconnections 

      Bakir, M. S.; Gaylord, T. K.; Ogunsola, O. O.; Glytsis, E. N.; Meindl, J. D. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, 2004-01)
      In the pursuit of high-density wafer-level input–output optical interconnections, microscopic polymer pillars have recently been fabricated. The optical performance of these pillars is critical for their potential ...
    • Optical-fiber-to-waveguide coupling using carbon-dioxide-laser-induced long-period fiber gratings 

      Bachim, Brent L.; Ogunsola, Oluwafemi O.; Gaylord, Thomas K. (Georgia Institute of TechnologyOptical Society of America, 2005-08)
      Optical fibers are expected to play a role in chip-level and board-level optical interconnects because of limitations on the bandwidth and level of integration of electrical interconnects. Therefore, methods are needed to ...
    • Optics in Energy: the power of optical solutions 

      Kippelen, Bernard (Georgia Institute of TechnologyOptical Society of America, 2010-04)
    • Optimal sliding correlator channel sounder design 

      Pirkl, Ryan J.; Durgin, Gregory D. (Georgia Institute of TechnologyInstitute of Electrical and Electronics Engineers, 2008-09)
      The sliding correlator technique remains one of the most versatile and effective methods for sounding the radio propagation channel in next-generation wireless systems. Despite their utility, there has never been a ...
    • Optimal sparse solution for fluorescent diffuse optical tomography: theory and phantom experimental results 

      Mohajerani, Pouyan; Eftekhar, Ali Asghar; Huang, Jiandong; Adibi, Ali (Georgia Institute of TechnologyOptical Society of America, 2007-04)
      We present a method to accurately localize small fluorescent objects within the tissue using fluorescent diffuse optical tomography (FDOT). The proposed method exploits the localized or sparse nature of the fluorophores ...
    • Optimization of anisotropically etched silicon surface-relief gratings for substrate-mode optical interconnects 

      Wu, Shun-Der; Gaylord, Thomas K.; Maikisch, Jonathan S.; Glytsis, Elias N. (Georgia Institute of TechnologyOptical Society of America, 2006-01)
      The optimum profiles of right-angle-face anisotropically etched silicon surface-relief gratings illuminated at normal incidence for substrate-mode optical interconnects are determined for TE, TM, and random linear (RL) ...
    • Optimization of finite-length input volume holographic grating couplers illuminated by finite-width incident beams 

      Wu, Shun-Der; Glytsis, Elias N.; Gaylord, Thomas K. (Georgia Institute of TechnologyOptical Society of America, 2005-07)
      A finite volume holographic grating coupler (VHGC) normally illuminated with various incident-beam profiles (such as a Gaussian beam, a flat cosine-squared beam, and an exponential-decay beam) with finite beam widths for ...
    • Optimization of sawtooth surface-relief gratings: effects of substrate refractive index and polarization 

      Wu, Shun-Der; Gaylord, Thomas K.; Glytsis, Elias N. (Georgia Institute of TechnologyOptical Society of America, 2006-05)
      The effect of the refractive index of the substrate together with the incident polarization on the optimization of sawtooth surface-relief gratings (SRGs) is investigated. The global optimum diffraction efficiencies of the ...
    • Optimizing organic photovoltaics using tailored heterojunctions: A photoinduced absorption study of oligothiophenes with low band gaps 

      Schueppel, R.; Schmidt, Karin; Uhrich, C.; Schulze, K.; Wynands, D.; Brier, E.; Reinold, E.; Bu, H.-B.; Baeuerle, P.; Maennig, B.; Pfeiffer, M.; Leo, K.; Brédas, Jean-Luc (Georgia Institute of TechnologyAmerican Physical Society, 2008-02)
      A power conversion efficiency of 3.4% with an open-circuit voltage of 1 V was recently demonstrated in a thin film solar cell utilizing fullerene C60 as acceptor and a new acceptor-substituted oligothiophene with an optical ...
    • Optimum parallel-face slanted surface-relief gratings 

      Maikisch, Jonathan S.; Gaylord, Thomas K. (Georgia Institute of TechnologyOptical Society of America, 2007-06)
      Using a combination of rigorous coupled-wave analysis and simulated annealing, parallel-face slanted surface-relief gratings (PFSSRGs) are optimized. For substrate-mode optical interconnects, profiles are presented for ...
    • Origin of the open-circuit voltage in multilayer heterojunction organic solar cells 

      Potscavage, William J., Jr.; Yoo, SeungHyup; Kippelen, Bernard (Georgia Institute of TechnologyAmerican Institute of Physics, 2008-11-10)
      From temperature dependent studies of pentacene/C₆₀ solar cells in the dark, the reverse saturation current is found to be thermally activated with a barrier height that corresponds to the difference in energy between the ...
    • Oscillations in meta-generalized-gradient approximation potential energy surfaces for dispersion-bound complexes 

      Johnson, Erin R.; Becke, Axel D.; Sherrill, C. David; DiLabio, Gino A. (Georgia Institute of TechnologyAmerican Institute of Physics, 2009-07)
      Meta-generalized-gradient approximations (meta-GGAs) in density-functional theory are exchange-correlation functionals whose integrands depend on local density, density gradient, and also the kinetic-energy density. It has ...
    • Passive all-optical polarization switch, binary logic gates, and digital processor 

      Zaghloul, Yasser A.; Zaghloul, A. R. M.; Adibi, Ali (Georgia Institute of TechnologyOptical Society of America, 2011-10)
      We introduce the passive all-optical polarization switch, which modulates light with light. That switch is used to construct all the binary logic gates of two or more inputs. We discuss the design concepts and the operation ...