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Showing 1 to 13 of 13 for “"hyperpolarizability"”.
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Evaluating optical nonlinearities and applications of photonic nanomaterials
… been found in TMD’s. A high value for the first hyperpolarizability of ZrTe2 monolayers suspended in acetonitrile (ACN) was measured using the HRS technique, and a dipolar behavior for the nonlinear polarization was demonstrated. It was characterized for the first time the nonlinear refraction …
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Designing and characterizing hyperpolarizable silicon nanoparticles for magnetic resonance imaging
… have the advantageous properties of hyperpolarizability and biodegradability, but in vivo utilization requires the modification of the particle surface to prevent aggregation that leads to very fast removal from circulation through phagocytosis by the liver, spleen, and lymph nodes. …
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NEW ORGANOMETALLIC COMPLEXES WITH PHOTOLUMINESCENT AND NON LINEAR OPTICAL PROPERTIES
… are characterized by a value higher o fquadratic hyperpolarizability than that of Disperse Red One, an NLO chromophore currently used in electro-optics polymers, and, moreover, they possess particular photostability. We also preliminarily investigated the second-order NLO response of both known …
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Enhancing the Third-Order Nonlinear Optical Properties of Porphyrins and Molecular Wires
… were investigated. The molecular second hyperpolarizability, γ, followed the power law γσ n2.12±0.05 (n is number of repeat units) for unusually large molecular lengths. The exceptional exciton delocalization length exceeds 360 conjugated bonds (>49 nm) and is attributed to the rigidity …
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Photonic Properties of Self -Assembled Organic Materials: Supramolecular Films, and Nanoribbon -Templated Gels and Polymers
… was found strongly influenced by molecular hyperpolarizability and layer spacing of the supramolecular materials formed by these molecules. The macroscopic polarization of these materials is relatively low, possibly caused by polydomain structures. To improve the polarization, glass …
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Organic Self-Assembled Films for Nonlinear Optics: Film Structure, Composition and Kinetics of Film Formation
… Brown (PB), which has a significantly higher hyperpolarizability than PCBS. It was found that a high pH, ~10.5, was important for achieving covalent attachment of the PB to the underlying PAH films. This resulted in much higher SHG intensities compared to when PB was deposited pH at 8.5-9.5 …
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Nonlinear Optical Properties and Structural Characteristics of Ionically Self-Assembled Nanoscale Polymer Films Influenced by Ionic Concentration and Incorporation of Monomer Chromophores
… films despite the very low first-order molecular hyperpolarizability beta of the incorporated monomer. This suggests that incorporation of high beta molecules may result in significant improvement of chi(2), holding high promise for the hybrid covalent / ionic self-assembly technique.
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SYNTHESIS AND CHARACTERIZATION OF NEW ORGANIC MOLECULES AND INORGANIC-ORGANIC HYBRID MATERIALS WITH INTERESTING LINEAR AND SECOND ORDER NON LINEAR OPTICAL PROPERTIES
… to chromophores in solution and the molecular hyperpolarizability has been determinate by EFISH technique. Of particular interest is the compound 8-N,N-dibutylamino-2-azachrysene which is characterized by a large hyperpolarizability value and very high thermal stability, properties that make it …
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Nonlinear Optical Response of Simple Molecules and Two-Photon Semiconductor Lasers
… nonlinear refractive index of air, and second hyperpolarizability of isolated CS2 molecules, are measured directly. The later agrees well with liquid CS2 measurements, where local field effects are significant. The second major portion of this dissertation addresses the possibility of using …
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Excited state charge redistribution and dynamics of flavins, flavorproteins, and their cofactors
… charge redistribution corresponds to a large hyperpolarizability of the chromophore that suggests that ABFL may be useful in nonlinear optical applications. Transient absorption was used to supplement these experiments by monitoring the decay kinetics of ABFL after excitation. It was found …
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Optical Limiting and Degenerate Four-Wave Mixing in Novel Fullerenes
… × 10⁻³² esu for the molecular second order hyperpolarizability, which is almost three orders of magnitude larger than the values reported in literature for an empty cage fullerene.
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Quantum Chemical Studies for the Engineering of Metal Organic Materials
… DFT calculations can predict the second order hyperpolarizability ?2 and tensor components necessary to estimate NLO. These calculations for the ?2 were done with the use of the Berry's finite field approach. An efficient material with high ?2 was designed and the resulting material was …
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Synthesis towards Polyhedral and Rigid Organic Non-Linear Optic Materials
<p>Currently, there is intense research interest in new molecular compounds that display enhanced second harmonic generation nonlinear optical (NLO) properties. Previous computational research has shown that both polyhedral carborane compounds and sterically constrained hydrindacene show great …