Silver optical properties

The preparation of the reflecting silver layers for MBI deserves special attention, since it affects the optical properties of the mirrors. Another important issue is the optical phase change [ ] at the mica/silver interface, which is responsible for a wavelength-dependent shift of all FECOs. The phase change is a fimction of silver layer thickness, T, especially for T < 40 mn [54]. The roughness of the silver layers can also have an effect on the resolution of the distance measurement [59, 60]. 

Bimetallic nanoparticles, either as alloys or as core-shell structures, exhibit unique electronic, optical and catalytic properties compared to pure metallic nanopartides [24]. Cu-Ag alloy nanoparticles were obtained through the simultaneous reduction of copper and silver ions again in aqueous starch matrix. The optical properties of these alloy nanopartides vary with their composition, which is seen from the digital photographs in Fig. 8. The formation of alloy was confirmed by single SP maxima which varied depending on the composition of the alloy. 

Lee, M.H., Dobson, P.J. and Cantor, B. (1992) Optical properties of evaporated small silver particles. Thin Solid Films, 219 (1-2), 199-205. 

Shalem S., German A., Barkay N., Moser F., Katzir A., Mechanical and optical properties of silver-halide infrared transmitting fibres, Fiber and integrated optics 1997 16 27-54. 

The remaining sections outline recent findings on the optical properties of metal-dendrimer nano-composites. The sections have been organized into areas of interest related to the fabrication as well as photophysical properties of these new and important materials. The first section discusses some of the important issues concerning the fabrication of these novel materials and their chemical characterization. The second section discusses the linear and nonlinear optical properties of these materials. The third section provides details related to the ultrafast emission properties of gold- and silver-dendrimer nanocomposites. 

Abstract Silver clusters, composed of only a few silver atoms, have remarkable optical properties based on electronic transitions between quantized energy levels. They have large absorption coefficients and fluorescence quantum yields, in common with conventional fluorescent markers. But importantly, silver clusters have an attractive set of features, including subnanometer size, nontoxicity and photostability, which makes them competitive as fluorescent markers compared with organic dye molecules and semiconductor quantum dots. In this chapter, we review the synthesis and properties of fluorescent silver clusters, and their application as bio-labels and molecular sensors. Silver clusters may have a bright future as luminescent probes for labeling and sensing applications. 

Adsorption of ions or molecules on metal clusters markedly affects their optical properties. It was shown that the intensity and the shape of the surface plasmon absorption band of silver nanometric particles, which is close to 380 nm, change upon adsorption of various substances [125]. The important damping of the band generally observed is assigned to the change of the electron density of the thin surface layer of the... 

Lu LH, Wang HS, Zhou YH, Xi SQ, Zhang HJ, Jiawen HBM, Zhao B (2002) Seed-mediated growth of large, monodisperse core-shell gold-silver nanoparticles with Ag-like optical properties. Chem Commun, pp 144-145... 

Maillard M, Giorgio S, Pileni M-P (2003) Tuning the Size of Silver Nanodisks with Similar Aspect Ratios Synthesis and Optical Properties. J Phys Chem 107 2466-2470... 

Roque J, Molera J, Sciau P, Pantos E, Vendrell-Saz M (2006) Copper and silver nanocrystals in lustre lead glazes development and optical properties. J European Ceramic Society 26 3813-3824. 

For optical applications requiring extreme clarity it is desirable to minimize silver streaking, and yellowing. For example, Topas 5013 can be modified pentaerythritol tetrastearate, pentaerythritol distearate, or zinc stearate in order to improve the optical properties (59). These blends are suitable for high precision optical applications. 

Following these studies were a series of works which examined the SH response from polycrystalline and crystalline silver electrode surfaces biased within the ideally polarizable region [42-44, 54-64], These studies showed the sensitivity of SHG to adsorption of ions to the electrode surface. More importantly, they showed that the sensitivity arose from the changes in the optical properties of the electrode surface itself, and not from the optical properties of the ionic and simple molecular species at the surface. Conversely, the SH response from an adsorbate, such as a dye molecule, can become an important factor if either the fundamental or SH photon energy is resonant with electronic transitions in the adsorbate [65, 66]. For more details on these SH studies of both ORC effects and adsorption phenomena on polycrystalline substrates, the reader is referred to Refs. 7 and 9. 

Gold possesses a unique combination of physical and optical properties. Its malleability, ductility and flexibility make it useful in industry as well as in ornamentation. As it is so soft, gold must be combined with other elements, usually silver, nickel, copper or palladium, before it can be used in coins or jewelry. Ancient gold objects may have a very high gold content because the metal was used just as it came out of the ground. 

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