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Estudo de propriedades ópticas não lineares de aminoácidos; Study of nonlinear optics property of amino acid

Rodrigues Junior, José Joatan
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 26/06/2003 PT
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Neste trabalho estudamos as propriedades ópticas não lineares de aminoácidos utilizando pulsos de laser com duração de femtossegundos. O índice de refração não linear (n2) da L-alanina, L-prolina, L-serina, L-treonina e L-arginina em solução aquosa foram determinados. Foi também estudada a influência do pH na magnitude de n2 dos aminoácidos em solução. Paralelamente, determinamos a dispersão de n2 em cristais de L-treonina nos três eixos principais, x, y e z. Os aminoácidos têm despertado grande interesse devido as suas boas propriedades ópticas de segunda ordem. Todavia, suas propriedades ópticas de terceira ordem ainda não haviam sido estabelecidas. Além disso, implementamos a técnica de espalhamento hiper-Rayleigh para determinar a primeira hiperpolarizabilidade (P) de moléculas orgânicas, onde uma mudança foi introduzida para permitir medidas mais rápidas e com melhor precisão. Foram encontrados os valores de P de algumas porfirinas e corantes orgânicos.; In this work we have studied nonlinear optical properties of amino acids using femtosecond laser pulses. The nonlinear index of refraction (nz) of L-alanine, L-proline, L-serine, L-threonine and L-arginine in aqueous solution have been determined. Also...

Metal Acetylides for NonLinear Optics: First Hyperpolarizabilities of Fe (II), Ru (II) and Ni (II) bearing Nitro Substituted Thienyl Chromophores

Mendes, Paulo J.
Fonte: XIX EuCHEMS Conference on Organometallic Chemistry (EuCOMC) Publicador: XIX EuCHEMS Conference on Organometallic Chemistry (EuCOMC)
Tipo: Artigo de Revista Científica
ENG
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Nonlinear Optics deals with the modification of material properties under the influence of intense light beams, resulting in processes that manipulate the amplitude, phase, polarization and frequency of emergent optical beams [1]. NLO materials find important applications in various photonic technologies as electro-optic switching devices for telecommunication, optical information processing and laser technology. The search and design of highly effective molecules for NLO applications, namely second harmonic generation (SHG) is therefore an important issue. Our studies concerning organotransition metal complexes of group VIII metals combined with heterocyclic π-conjugated chromophores in an asymmetric push-pull fashion, have shown first hyperpolarizability (ß) values that suggest promising SHG effects [2,3]. Herein, we describe the synthesis, spectroscopic and electrochemical characterization of six new η5-monocyclopentadienyliron (II), ruthenium (II) and nickel (II) σ-acetylide complexes bearing nitro substituted thienyl chromophores. The ß parameter was measured at 1500 nm, in chloroform solutions, by means of Hyper-Rayleigh Scattering technique [4]. Our results show that ß parameter is strongly dependent on the metal center and the conjugated π-system of the organic chromophore. In order to assess possible structure-activity correlations...

Syntheses and characterization of η5-monocyclopentadienylruthenium(II) complexes with thienyl acetylide chromophores for nonlinear optics

Mendes, Paulo J.
Fonte: XXth Meeting of the Portuguese Society of Chemistry Publicador: XXth Meeting of the Portuguese Society of Chemistry
Tipo: Aula
ENG
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Over the past 20 years, there has been a growing interest in the design and synthesis of organic and organometallic molecules for the development of novel nonlinear optical (NLO) materials owing to their potential application in the area of integrated optics.1 Ultimately, these materials could be used with enhanced efficiency and versatility in areas such as optical communications, computing and data storage. Fundamental research has been focused in the establishment of detailed structure–activity correlations in view to obtain large intrinsic optical nonlinearities. For second-order nonlinear optics, this lead to the development of typical push-pull systems in which the metal center, bonded to a hyperpolarizable organic chromophore, acts as an electron releasing or withdrawing group. Among the organometallic compounds presenting this structural feature, systematic studies were made on half-sandwich complexes presenting benzene-based chromophores bonded to the metal center via nitrile or acetylide linkages.2,3 The results revealed that the compounds possessing acetylide ligands have better NLO properties than the nitrile analogues. In addition, recent results on half-sandwich complexes presenting thiophene nitrile chromophores showed an enhanced NLO performance when compared to that observed on analogue benzenoid structures.4 These results suggest that combination of acetylide thiophene ligands with appropriate organometallic fragments would maximize the NLO response. Thus...

6.161 Modern Optics Project Laboratory, Fall 2002; Modern Optics Project Laboratory

Warde, Cardinal
Fonte: MIT - Massachusetts Institute of Technology Publicador: MIT - Massachusetts Institute of Technology
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Lectures, laboratory exercises, and projects in modern optics. Topics: polarization properties of light, reflection and refraction, coherence and interference, Fraunhofer and Fresnel diffraction, imaging and transforming properties of lenses, spatial filtering, coherent optical processors, holography, optical properties of materials, lasers, nonlinear optics, electro-optic and acousto-optic materials and devices, optical detectors, fiber optics, and optical communication. Students may use this subject to find an advanced undergraduate project and/or to satisfy Phase II of the writing requirement.

Materials for nonlinear optics : semicontinuous gold films and fast saturable absorbers

Piredda, Giovanni (1970 - ); Boyd, Robert W. (1948 - )
Fonte: University of Rochester. Publicador: University of Rochester.
Tipo: Tese de Doutorado Formato: Number of Pages:xvii, 156 leaves
ENG
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Thesis (Ph. D.)--University of Rochester. Institute of Optics, 2008.; In this thesis I have investigated two types of materials that have the potentiality, in different ways, to contribute to practical applications of nonlinear optics: semicontinuous gold films and fast saturable absorbers. Metals have extremely high values of the third-order nonlinear optical susceptibility (they are approximately 106 times more nonlinear than silica) and a very fast response time (on the order of 2 ps); this high nonlinearity makes them attractive candidates for applications such as all-optical switching. On the other hand, as everyday experience teaches, they do not let light pass through. One way to make light penetrate more deeply into metals is mixing them with dielectrics. In particular in my thesis I have studied the nonlinear properties of collection of gold nanoparticles embedded into silica or deposited onto it. These nanoparticle systems possess special resonances, the "plasmon resonances", that are absent from either bulk metal or bulk dielectric but only arise when the two are combined at the nanoscale. In the linear optical response these resonances produce extinction bands that for gold in silica are situated in the visible. At the resonance wavelength the electric field is concentrated inside the nanoparticles...

Nonlinear optics: the next decade

Kivshar, Yuri
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Journal article; Published Version Formato: 3 pages
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This paper concludes the Focus Serial assembled of invited papers in key areas of nonlinear optics (Editors: J.M. Dudley and R.W. Boyd), and it discusses new directions for future research in this field.

Frequency-selective self-trapping and supercontinuum generation in arrays of coupled nonlinear waveguides

Babushkin, Ihar; Husakou, Anton; Herrmann, Joachim; Kivshar, Yuri
Fonte: Universidade Nacional da Austrália Publicador: Universidade Nacional da Austrália
Tipo: Journal article; Published Version Formato: 6 pages
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We study spatiotemporal dynamics of soliton-induced twooctave- broad supercontinuum generated by fs pulses in an array of coupled nonlinear waveguides. We show that after fission of the input pulse into several fundamental solitons, red and blue-shifted nonsolitonic radiation, as well as solitons with lower intensity, spread away in transverse direction, while the most intense spikes self-trap into spatiotemporal discrete solitons.

Nonlinear optics in titanium dioxide: from bulk to integrated optical devices

Evans, Christopher Courtney
Fonte: Harvard University Publicador: Harvard University
Tipo: Thesis or Dissertation
EN_US
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In this thesis, we explore titanium dioxide (TiO2) for ultrafast, on-chip nonlinear optics by studying it in bulk, thin films, and in integrated nonlinear optical devices. TiO2's large nonlinear index of refraction (30 times that of silica) and low two-photon absorption can enable all-optical switching, logic, and wavelength conversion across wavelengths spanning the telecommunications octave (800–1600 nm). In addition, its high linear index of refraction can enhance optical confinement down to nano-scale dimensions and facilitate the tight waveguide bends necessary for dense on-chip integration. Throughout this thesis, we develop TiO2 as a novel on-chip nonlinear optics platform.; Engineering and Applied Sciences

Efficient photon counting and single-photon generation using resonant nonlinear optics

Johnsson, Mattias; Fleischhauer, Michael
Fonte: American Physical Society Publicador: American Physical Society
Tipo: Artigo de Revista Científica
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A study on efficient photon counting and single-photon generation using resonant nonlinear optics is presented. The behavior of an atomic double λ system is examined in the presence of a strong off-resonant classical field and a few-photon resonant quant

Nonlinear optics and optical limiting properties of multifunctional fullerenol/polymer composite

Elim, Hendry Izaac; Ji, Wei; Meng, Gwee Chen; Ouyang, Jianying; Goh, Suat Hong
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 11/12/2002
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The nonlinear optics and optical limiting properties of materials based on multifunctional fullerenol and poly(styrene-co-4-vinylpyridine) matrix were studied using 7 ns pulses of nanosecond laser operating at 532 nm wavelength. The observed imaginary and real parts of third order susceptibility of the fullerenol/polymer composite are found to be lower than that of its parent C60. The optical limiting performances of fullerenol and fullerenol incorporated with poly(styrene-co-4-vinylpyridine) have been proved to be poorer than that of C60 due to their higher limiting thresholds. Concentration dependence of poly(styrene-co-4-vinylpyridine) containing 32 mol% has been mainly contributed to the optical limiting performance of fullerenol.; Comment: 23 pages, 9 figures, presented in ISMOA-2002, Bandung, Indonesia. Submitted to J. Nonlinear Opt. Phys. (December 2002)

Multistep Parametric Processes in Nonlinear Optics

Saltiel, Solomon M.; Sukhorukov, Andrey A.; Kivshar, Yuri S.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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We present a comprehensive overview of different types of parametric interactions in nonlinear optics which are associated with simultaneous phase-matching of several optical processes in quadratic nonlinear media, the so-called multistep parametric interactions. We discuss a number of possibilities of double and multiple phase-matching in engineered structures with the sign-varying second-order nonlinear susceptibility, including (i) uniform and non-uniform quasi-phase-matched (QPM) periodic optical superlattices, (ii) phase-reversed and periodically chirped QPM structures, and (iii) uniform QPM structures in non-collinear geometry, including recently fabricated two-dimensional nonlinear quadratic photonic crystals. We also summarize the most important experimental results on the multi-frequency generation due to multistep parametric processes, and overview the physics and basic properties of multi-color optical parametric solitons generated by these parametric interactions.; Comment: To be published in Progress in Optics

Time-reversed wave mixing in nonlinear optics

Zheng, Yuanlin; Ren, Huaijin; Wan, Wenjie; Chen, Xianfeng
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 14/01/2013
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Time-reversal symmetry is important to optics. In linear optics, a time-reversed process to laser emission enables total absorption of coherent light fields into an optical cavity of loss by time-reversing the original gain medium. In nonlinear optics, time symmetry exists for some well-known processes such as parametric up/down conversion, sum/difference frequency generation, however, combining exact time-reversal symmetry with nonlinear wave mixings is yet explored till now. Here, we demonstrate time reversed wave mixings for second harmonic generation (SHG) and optical parametric amplification (OPA). This enables us to observe the annihilation of coherent beams under time-reversal symmetry by varying the relative phase of the incident fields. Our study offers new avenues for flexible control in nonlinear optics and potential applications in efficient wavelength conversion, all-optical computing.; Comment: 18 pages, 4 figures

The arrow of time in quantum mechanics and in nonlinear optics

Kuz'menko, Vladimir A.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 03/06/2005
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The direct and indirect experimental proofs of a strong time invariance violation in optics are discussed. Time noninvariance for present day becomes the only real physical base for explanation the origin of the most phenomena in nonlinear optics. This is a good cause to introduce the time asymmetry into the dynamical equations of the basic laws of physics.; Comment: 7 pages, 2 figures, talk for sixth international conference - Symmetry in Nonlinear Mathematical Physics, June 20-26, 2005, Kiev, Ukraine

Platforms for integrated nonlinear optics compatible with silicon integrated circuits

Moss, David J.; Morandotti, Roberto
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 28/10/2014
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Nonlinear photonic chips are capable of generating and processing signals all-optically with performance far superior to that possible electronically - particularly with respect to speed. Although silicon has been the leading platform for nonlinear optics, its high two-photon absorption at telecommunications wavelengths poses a fundamental limitation. We review recent progress in CMOS-compatible platforms for nonlinear optics, focusing on Hydex glass and silicon nitride and briefly discuss the promising new platform of amorphous silicon. These material systems have opened up many new capabilities such as on-chip optical frequency comb generation, ultrafast optical pulse generation and measurement. We highlight their potential future impact as well as the challenges to achieving practical solutions for many key applications.; Comment: 53 pages, 109 references, 21 figures, book chapter. arXiv admin note: substantial text overlap with arXiv:1404.3775

Scale-invariant nonlinear optics in gases

Heyl, C. M.; Coudert-Alteirac, H.; Miranda, M.; Louisy, M.; Kovacs, K.; Tosa, V.; Balogh, E.; Varjú, K.; L'Huillier, A.; Couairon, A.; Arnold, C. L.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 04/09/2015
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Nonlinear optical methods are becoming ubiquitous in many areas of modern photonics. They are, however, often limited to a certain range of input parameters, such as pulse energy and average power, since restrictions arise from, for example, parasitic nonlinear effects, damage problems and geometrical considerations. Here, we show that many nonlinear optics phenomena in gaseous media are scale-invariant if spatial coordinates, gas density and laser pulse energy are scaled appropriately. We develop a general scaling model for (3+1)-dimensional wave equations, demonstrating the invariant scaling of nonlinear pulse propagation in gases. Our model is numerically applied to high-order harmonic generation and filamentation as well as experimentally verified using the example of pulse post-compression via filamentation. Our results provide a simple recipe for up-or downscaling of nonlinear processes in gases with numerous applications in many areas of science.; Comment: This manuscript has 9 pages including 3 figures and two tables

Turing Patterns in Nonlinear Optics

Staliunas, Kestutis; Sanchez-Morcillo, Victor J.
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
Publicado em 16/02/2000
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The phenomenon of pattern formation in nonlinear optical resonators is commonly related to an off-resonance excitation mechanism, where patterns occur due to mismatch between the excitation and resonance frequency. In this paper we show that the patterns in nonlinear optics can also occur due to the interplay between diffractions of coupled field components. The reported mechanism is analogous to that of local activation and lateral inhibition found in reaction-diffusion systems by Turing. We study concretely the degenerate optical parametric oscillators. A local activator-lateral inhibitor mechanism is responsible for generation of Turing patterns in form of hexagons.; Comment: 11 pages, 5 figures, submitted to Optics Communications

All-optical signal processing platforms for CMOS compatible integrated nonlinear optics

Morandotti, Roberto; Moss, David J.; Gaeta, Alexander L.; Lipson, Michal
Fonte: Universidade Cornell Publicador: Universidade Cornell
Tipo: Artigo de Revista Científica
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Nonlinear photonic chips have enabled the generation and processing of signals using only light, with performance far superior to that possible electronically - particularly with respect to speed. Although silicon-on-insulator has been the leading platform for nonlinear optics, its high two-photon absorption at telecommunications wavelengths poses a fundamental limitation. We review recent progress in non-silicon CMOS-compatible platforms for nonlinear optics, with a focus on Si3N4 and Hydex. These material systems have opened up many new capabilities such as on-chip optical frequency comb generation and ultrafast optical pulse generation and measurement. This review highlights their potential impact as well as the challenges to achieving practical solutions for many key applications.; Comment: Review Paper, 31 pages, 129 references, 6 figures

Dynamics of spatial structures in nonlinear optics

Gomila, Damià
Fonte: Universidad de las Islas Baleares Publicador: Universidad de las Islas Baleares
Tipo: Tesis Formato: 5898264 bytes; application/pdf
ENG
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Tesis doctoral de la Universidad de las Islas Baleares,Instituto Mediterráneo de Estudios Avanzados (IMEDEA-CSIC/UIB).-- Texto en inglés, agradecimientos en catalán.-- 181 pages, 3 appendixes.-- Fecha de lectura: 11-02-2003.; The formation of spatial structures in systems out of thermodynamical equilibrium has been the subject of a large amount of scienti c research in the last quarter of the 20'th century [101, 39, 245]. Examples include patterns in hydrodynamic systems, granular media, nonlinear optics, oscillatory chemical reactions and biological systems. De nite progress has been made in the understanding of the common general theory behind the emergence and evolution of spatial structures. Methods of nonlinear dynamics and bifurcation theory such as amplitude equations, that describe the dynamics close to bifurcation points, or \phase equations", that describe the slow distortions of patterns even far from the instability threshold, have been essential tools in the development of a universal description of pattern formation and their dynamics.However, these analytical techniques have limitations, and interesting phenomena often take place beyond their range of validity. For instance, instabilities of patterns (secondary bifurcations) may take place far away from the pattern formation instability where the dynamics of the systems is not properly reproduced by the the amplitude equations obtained at the primary instability. Furthermore...

Theory and design of nonlinear metamaterials

Rose, Alec Daniel
Fonte: Universidade Duke Publicador: Universidade Duke
Tipo: Dissertação
Publicado em //2013
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If electronics are ever to be completely replaced by optics, a significant possibility in the wake of the fiber revolution, it is likely that nonlinear materials will play a central and enabling role. Indeed, nonlinear optics is the study of the mechanisms through which light can change the nature and properties of matter and, as a corollary, how one beam or color of light can manipulate another or even itself within such a material. However, of the many barriers preventing such a lofty goal, the narrow and limited range of properties supported by nonlinear materials, and natural materials in general, stands at the forefront. Many industries have turned instead to artificial and composite materials, with homogenizable metamaterials representing a recent extension of such composites into the electromagnetic domain. In particular, the inclusion of nonlinear elements has caused metamaterials research to spill over into the field of nonlinear optics. Through careful design of their constituent elements, nonlinear metamaterials are capable of supporting an unprecedented range of interactions, promising nonlinear devices of novel design and scale. In this context, I cast the basic properties of nonlinear metamaterials in the conventional formalism of nonlinear optics. Using alternately transfer matrices and coupled mode theory...

Organometallic Complexes for Nonlinear Optics. 28. Dimensional Evolution of Quadratic and Cubic Optical Nonlineararities in Stilbenylethynylruthenium Complexes

Hurst, Stephanie; Humphrey, Mark; Isoshima, Takashi; Wostyn, Kurt; Asselberghs, Inge; Clays, Koen Jan; Persoons, Andre Pierre; Samoc, Marek; Luther-Davies, Barry
Fonte: American Chemical Society Publicador: American Chemical Society
Tipo: Artigo de Revista Científica
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The use of organometallic complexes for nonlinear optics was discussed. Cubic nonlinearities \γ\800 and two-photon absorption cross-sections σ2 increase on 'dimensional evolution' from linear analogues to octopolar complexes. Molecular third-order nonli