NLO materials

Table 1. Comparison of Electrooptic Modulator Performance Parameters of NLO Materials ...

Materials for Frequency Doubling. Second-order NLO materials can be used to generate new frequencies through second harmonic generation (SHG), sum and difference frequency mixing, and optical parametric oscillation (OPO). The first, SHG, is given in equation 3. 

Materials. NLO materials possess a high degree of optical nonlinearity, physical durabiHty and chemical inertness, and high threshold to optical damage. In addition, it must be possible to process the materials into the form required by the intended appHcation. 

Fig. 2. Optical nonlinearity and phase matching windows for commonly used NLO materials. KDP = KH2PO4 BBO = j3 — BaB2 KTP = KTiOPO. ...

Polymers and supermolecules modified using electron push-pull chro-mophores are also of particular interest for nonlinear optics (NLO) [10-15]. NLO material has attracted much interest over the past 20 years and has been widely applied in various field (telecommunications, optical data storage, information processing, microfabrication, etc.). Chemists have developed ways to introduce NLO chromophores into many type of polymers, such as Hnear polymers, cross-linked polymers, and branched polymers, and have demonstrated their performance in NLO appHcations. 

Some quinones, having the ability to form intra- and/or intermolecular hydrogen bonds, exhibit high molecular hyperpolarizability and are third-order nonlinear optical (NLO) materials. Compound 39 has a %(3) of 5 x 10 11 esu at 1.9 pm, and is a third-order NLO material.23 The optoelectric properties of quinoid compounds correlate with their structures in crystals or on thin films.23... 

NLO materials (16 and 17) (Fig. 13) have been obtained from polyurethanes by the incorporation of sidechains with boron chromophores.37 The dihydroxy ligand of an azobenzene ligand containing a dimesityl boron acceptor was reacted in a polycondensation fashion with the diisocyanate groups of the polyurethanes to yield the desired polymers. Halogen displacement and transmetallation reactions have been utilized in the development of extended ir-conjugated systems of tri-9-anthrylborane with dendritic structures.38 In one (18) (Fig. 14) of the novel compounds, three identical... 

The initial stages in the development of novel molecular NLO materials are the synthesis of molecules with large j3 and/or 7 values and their incorporation into materials with substantial x(2) and/or X 3) coefficients. Although many additional factors must be considered for practical device... 

NLO materials which necessitate operation at off-resonance wavelengths, generally in the NIR region ca. 1,000-1,500 nm. 

Numerous compounds of the types (L)AuC=CR and Q+[Au(C=C-R)2] were investigated for their properties as NLO materials. Some of the examples were found to have the largest cubic optical non-linearity for monomeric organometallics.103 Examples are given in Scheme 18. For all of these compounds, the quadratic/cubic hyperpolarizability (linear optical and quadratic NLO response) have been determined. The studies were complemented by cyclovoltammetric measurements.58,59,103,112-117... 

Carbenes form stable complexes with many metals in the periodic table of the elements, and gold is no exception. In fact, the chemistry of this class of organogold compounds for some time has been one of the fastest growing subdisciplines. While the corresponding chapters were still short in previous accounts,1 2 the inventory for this review is now particularly rich and diverse.230 As for other classes of carbene complexes, this upsurge is based on expectations for potential applications in various fields such as NLO materials, liquid crystalline phases, and catalysis. Where applicable, this is indicated for each of the entries in this chapter. 

The ethynyl-linked complexes 105 were prepared and explored as potential building blocks for nonlinear optical (NLO) materials.129 Spectroscopic and cyclic voltammetry data indicate a small but real interaction between the ferrocenyl donor group and the borabenzene unit, increasing in the order RuHyper-Rayleigh scattering revealed small values for the first hyperpolarizability / , which increases in the same order. 

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