Optical switching devices

Blom, F.C., vanDijk, D.R., Hoekstra, H.J.W.M., Driessen, A., and Popma, T.J.A., 1997, Experimental study of integrated-optics microcavity resonators Toward an all-optical switching device., Appl. Phys. Lett. 71(6) 747-749. 

The fabrication process of vanadium oxide (VO2) has also been studied using RBS/C. Since optieal and electrical properties of VO2 are dramatically changed at 68°C due to phase transition, VO2 is regarded as one of the candidates for thermally activated electronic or optical switching devices for optieal fibers or sensors. To obtain the desired properties, the development of the fabrication process for very thin films, without crystalline defects on various substrates, is required. Single-crystalline VO2 thin films on (0001) plane of a sapphire substrate have been synthesized by a laser ablation method. The quality of VO2 was examined by X-ray diffraction and RBS/C method. The eleetrieal resistanee and the optical transmittance of the VO2 film were measured under inereasing and deereasing temperatures. At a temperature of 68 °C, an abrupt transition of resistanee from metal to... 

Poly(2-vinylpyridinc)- >-poly(w-bcxylisocyanatc), (I), was prepared by the authors (2) by living polymerization using potassium diphenylmethane as initiator and then adding sodium tetraphenylborate to replace the counter cation with a sodium ion. The product was used in optical applications such as an optical switch device. 

Experimental work and theoretical investigation show an important role of spatial chaos in optical fibers, directional couplers, and generally in all-optical switching devices [96/97]. 

FIG. 7.21 An optical switching device based on Langmuir-Blodgett films. (Redrawn with permission of P. Ball 1994.)... 

Some of the latest work on high refractive index polyphosphazenes makes use of polymers that contain both fluoroalkoxy and di- or tri-chlorophenoxy side groups.261 These amorphous glasses are thermally stable up to 400 °C, show a large variation of refractive index with temperature, and refractive index values that vary from 1.39-1.56 depending on composition. Thus, they are candidates for uses in thermo-optical switching devices. 

S. L. Gilat, S. H. Kawai, and J.-M. Lehn, Light-triggered electrical and optical switching devices, J. Chem. Soc. Commun. 1993, 1439—1442. 

For symmetry reasons, the first macroscopic nonlinear coefficient is zero in unordered polymer materials. On the other hand, azo-dye polymers can exhibit very large values, which is interesting for applications in optical limiting and optical switching devices. We will consider the relationship between microscopic and macroscopic third-order susceptibilities. The most general equation for this relationship can be written as ... 

Hoshino, M., Ebisawa, F., Yoshida, T., and Sukegawa, K. Refractive index change in photochromic diarylethene derivatives and its application to optical switching devices. J. Photochem. Photobiol. A Chem. 1997, 105, 75. 

Photoinduced processes and resonant third order nonlinearity in poly(3-dodecylthiophene) has been studied by fs time resolved 4-wave mixing . Similar work has been reported for the poly(p-phenylene vinylene) system . Such materials have potential for the use as nonlinear optical switching devices. 

Near resonant z-scan studies provide both nonlinear refractive coefficients, ni, and two photon absorption coefficients, p. Results for a selection of PDAs in solution at 532 nm are given in Table 1. Diethylamino-PDA (lid) and the related quatemized polymer (15a) show comparable magnitudes of nonlinear absorption and refraction to those of poly-4-BCMU, with figures of merit, T, which satisfy the requirement for nonlinear optical switching devices. The metal-containing PDAs... 

Ouwerkerk, M Janner, A.-M., Van Der Sluis, P Mercier, V.M.M. pCXXX) Optical switching device. United States patent application 20030227667. 

Suitable solvent systems for MNA were identified for the solutiorvbased all-optical switching device. Dlmethylformamide (DMF), p-dioxane, propylene carbonate (PC) and tetrahydrofuran (THF) provided high solubility with a wide range of index choices. Solubility of MNA in each solvent (HPLC grade) at room temperature was measured for the determination of the range of refractive index available (Table 1). 

Conjugated polymers demonstrate reasonable electrical conductivity which can be used in antistatic coatings, electronic devices, batteries, electromagnetic interference (EMI) shielding, electrochromic devices, optical switching devices, sensors, and textiles. ... 

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