Etude des effets optiques du deuxième et troisième ordre photo induits dans des complexes alkynyls à base de ruthénium

Ce travail de thèse est consacré aux études théoriques et expérimentales des effets optiques non linéaires du second et troisième ordre photo induits dans de nouveaux complexes alkynyls à base de ruthénium. L objectif principal de ce travail est de déterminer l influence des structures chimiques des composés organométalliques fonctionnalisées sur les propriétés optiques non linéaires du 2ème et 3ème ordre à l aide des techniques de poling optique de génération du second harmonique (PISHG), de génération du second harmonique optique induite acoustiquement (AIOSHG) et du mélange quatre ondes dégénéré (DFWM). Nous avons démontré l influence de la matrice sur la cinétique des processus optiques non linéaires du 3ème ordre dans les complexes organométalliques. Nous avons démontré que l incorporation des dérivés ruthénium-alkynyl dans des matrices polymères (PVK et PMMA) entraîne une augmentation des propriétés optique non linéaires et que leur rôle est crucial dans la compréhension des phénomènes observés. Un bon accord entre les résultats expérimentaux et les simulations est obtenu. Il s agit d une contribution à la fois importante et utile dans le domaine des matériaux fonctionnels car nous avons démontré que ces composés sont multifonctionnels et l originalité de ce travail consiste surtout en un choix judicieux des composés suivant leur potentialité d application en optoélectronique.The thesis is devoted to the theoretical and experimental studies of Photo-induced second and third order optical effects in ruthenium alkynyl push pull complexes. The main goal of this work was to determine the influence of the chemical structures of the organometallic compounds on the second and third-order nonlinear optical properties using optically and acoustically induced second harmonic generation (AISHG) and degenerate four wave mixing (DFWM) experiments. The investigation of kinetics of the third order nonlinear optical processes in organometallic complexes is also presented. The alkynyl ruthenium derivatives were embedded in polymethyl methacrylate (PMMA) and polyvinylcarbazole (PVK) polymer matrix. We showed that the influence of the polymer matrix play crucial role for the kinetics of the observed behaviour in the Ru-containing chromophore. The originality of this work consists especially on judicious choice of studied compound according to their potential applications in optoelectronics. We showed a good correlation between the chemical structures and the nonlinear optical properties. We also demonstrate their potentiality for the applications in nonlinear optics (SHG, AISHG,THG) and recently as like optical memories in picoseconds regime.ANGERS-BU Lettres et Sciences (490072106) / SudocSudocFranceF

Some selected and fonctionalized organometallic nanocomposites for NLO applications

Date du colloque&nbsp;: 09/2008</p

Some selected and fonctionalized organometallic nanocomposites for NLO applications

Date du colloque&nbsp;: 09/2008</p

Selected Organometallic Compounds for Third Order Nonlinear Optical Application

In this paper, we present the third harmonic generation response of Znq2 (Bis-(8-hydroxyquinolinato)zinc), Cuq2 (8-Hydroxyquinoline copper(II)), and Alq3 (Tris-(8-hydroxyquinoline)aluminum) organometallic compounds. An experiment was conducted for s and p polarizations of incident beam, using the Maker fringes technique. The third order nonlinear susceptibility &#967;(3) was estimated using the Kubodera and Kobayashi comparative model, on the grounds that presented compounds exhibit high linear absorption of the generated third harmonic wavelength (355 nm). These complexes were deposited as thin films using the physical vapor deposition (PVD) method. Investigated complexes vary in terms of the coordination center and number of quinoline ligands, which visibly influence their nonlinear response. The global hybrid B3LYP functional with the basis set 6-31G(d) was used in computing the linear and non-linear optical properties. The computed &#947;tot value (8765.36 &#215; 10&#8722;36 esu for Cuq2) is superior to that of methylene blue (&#947; = 32.00 &#215; 10&#8722;36 esu). The calculated theoretical values were found to be in good agreement with the experimental results

Nonlinear optical refractive index and absorption of coordination compounds

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