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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Synthesis, characterization and NLO properties of octupolar molecules /

Hu, Quanyuan. January 2005 (has links)
Thesis (Ph.D.)--Hong Kong University of Science and Technology, 2005. / Includes bibliographical references. Also available in electronic version.
2

Mapping the atmosphere for pulse propagation

Pape, Louis Edward, 1948- January 1972 (has links)
No description available.
3

Photonic Crystals with Active Organic Materials

Wu, Yeheng January 2010 (has links)
Thesis(Ph.D.)--Case Western Reserve University, 2010 / Title from PDF (viewed on 2010-04-12) Department of Physics Includes abstract Includes bibliographical references and appendices Available online via the OhioLINK ETD Center
4

High intensity beam propagation in media with strong nonlinearities

Polyakov, Sergey Vladimirovich 01 April 2003 (has links)
No description available.
5

Multiphoton effects in the polydiacetylene poly bis(p-toluene sulfonate) of 2,4-hexadiyne-1,6-diol (pts)

Yoshino, Fumiyo 01 April 2003 (has links)
No description available.
6

Enhancing chiroptical signals from metamaterials via nonlinear excitation

Rodrigues, Sean Phillip 07 January 2016 (has links)
As natural chiral materials demonstrate limited circularly dichroic contrasts, enhancement of these polarization dependent signals has long been the focus of chiral metamaterial research. By manipulating the geometric chirality of resonant plasmonic nanostructures, we are capable of enhancing light confinement to amplify chiral modified, nonlinear signals from quantum emitters. The metamaterial demonstrates a linear transmission contrast of 0.5 between left and right circular polarizations and a 20× contrast between second harmonic responses from the two incident polarizations. Nonlinear and linear response images probed with circularly polarized lights show strongly defined contrast. As a second set of experimentation, the chiral center of the metamaterial is opened, providing direct access to place emitters to occupy the most light-confining and chirally sensitive regions. The resulting two-photon emission profiles from circularly polarized excitation displays mirrored symmetry for the two enantiomer structures. The efficiency of the nonlinear signal directly correlates to the chiral resonance of the linear regime. The nonlinear emission signal is enhanced by 40× that of the emitters not embedded in the metamaterial and displays a 3× contrast for the opposite circular polarization. Such manipulations of nonlinear signals with metamaterials open pathways for diverse applications where chiral selective signals are monitored, processed, and analyzed.
7

FUNDAMENTAL LIMITATIONS ON THE OPERATION OF OPTICAL BISTABLE DEVICES IN A RING CAVITY AND IN GALLIUM-ARSENIDE ETALONS.

OVADIA, SHLOMO. January 1984 (has links)
The fundamental limitations on the operation of optical bistable devices in a ring cavity and in GaAs etalons are investigated. Experimental results of spontaneous transitions due to shot noise fluctuations are found in good agreement with various "ladder" models, if one allows the counting rates to vary accordingly. Stability analysis for two-photon homogeneously broadened media reveals single-wavelength instabilities for the laser but not for absorptive optical bistability. Appreciable regions of sidemode gain exist for both problems allowing for multiwavelength instabilities to occur. GaAs bistable devices show attractive features such as low power and high speed at room temperature for optical processing. However, experimental evidence in GaAs confirm the computer simulations of bistability that cavity losses, due to unsaturable background absorption, limit the switching power at room temperature. Methods to overcome the different limitations in GaAs devices toward parallel computation are then addressed from a system approach.
8

NONLINEAR OPTICAL TRANSVERSE EFFECTS: CW ON-RESONANCE ENHANCEMENT, CW OFF-RESONANCE INTERFERENCE RINGS, CROSSTALK, INTRACAVITY PHASE SWITCHING, SELF-DEFOCUSING IN GALLIUM-ARSENIDE BISTABLE ETALON, SELF-FOCUSING AND SELF-DEFOCUSING OPTICAL BISTABILITY, AND INSTABILITIES (SODIUM VAPOR, WAVE PROPAGATION, OPTICAL CHAOS).

TAI, KUOCHOU. January 1984 (has links)
Nonlinear optical transverse effects, which arise from the interaction of a Gaussian beam with a nonlinear medium, are discussed. They are cw on-resonance enhancement (CORE), cw off-resonance rings, crosstalk, intracavity phase switching, self-defocusing of a bistable etalon, and thin-sample-encoding (TSE) self-lensing (i.e., self-focusing or self-defocusing) bistability and instabilities. CORE is the enhancement of the on-axis intensity of an on-resonance laser beam in a two-level medium. We report the first observation of CORE using sodium vapor. Cw off-resonance rings, resulting from a pure phase encoding or from simultaneous phase and amplitude encodings, are observed using sodium vapor. These rings have been observed many time before, but we have made the first careful comparison with numerical calculations. Parallel operation and external switching are two crucial themes for the application of bistable optical devices (BODs). For parallel operation, crosstalk between nearby BODs on the same etalon due to diffraction coupling may need to be avoided. Minimum separations needed to ensure independent operation are computed. For external switching, intracavity phase switching using a plane-wave input can switch on (or off) a BOD using an external pulse. The validity of this concept for a Gaussian input is numerically simulated. Self-defocusing effects, resulting in some interesting effects in the transverse bistable loops, are observed using a GaAs-GaAlAs bistable etalon. The results are confirmed by numerical simulations. TSE self-lensing bistability is observed using a short sodium cell and a single mirror. TSE self-lensing bistability results from an enhancement in the feedback via self-lensing of the beam. The lack of an optical resonator and the use of a thin medium make TSE setup a good candidate to study the Ikeda instability. We report the first observation of the Ikeda instability in this all-optical passive system using a cw input. Numerical simulations show a rich bifurcation sequence not yet fully studied experimentally.
9

TRANSVERSE EFFECTS IN THREE-WAVE MIXING.

Stuut, Stephen Unko. January 1983 (has links)
No description available.
10

Bimetallic organoiron dipoles as NLO materials

Simpkins, Simon M. E. January 2001 (has links)
No description available.

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