New Version of Laser Device Materials for Developing Diffraction Beam Modulators; Novel Nano-periodic Structures
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1176-Y06-12
New Version of Laser Device Materials for Developing Diffraction Beam Modulators; Novel Nano-periodic Structures
Kyung M. Choi* and Kenneth J. Shea Chemistry, University of California, Irvine, CA 92697 [email protected] Cro/CrOx doped hybrid glasses are designed to develop novel laser device materials by inserting alkylene spacers between inorganic oxides. In TEM images, morphology of the organically modified hybrid glasses reveals highly arranged nanoperiodic patterns. The nanopatterns observed from the hybrid glass based on alkylene-bridged xerogel are sustained over substantial domains and appears to arise from modified glassy lattice fringes. In electron diffraction pattern, it also shows the circled diffraction patterns arise from Cro/CrOx. In laser experiments, the hybrid glass shows a new optical property, which generates a huge acoustic wave; the diffraction efficiency (45 %) of the modified glass is higher than that of methanol (25 %); it means that the compressibility of the solid type of glass is as effective as the liquid. The hybrid glass shows a new optical property that hitherto hasn’t been found and could be useful for developing diffraction beam modulators.
Introduction In this study, an optically transparent organic/inorganic hybrid glass doped with a composite of chromium/chromium oxides has been synthesized by sol-gel copolymerization. Sol-gel technology allows the tailoring of optical properties in organically modified hybrid glasses for use 1-9
in new laser device materials. For example, sol-gel glasses have been prepared as high gain photorefractive materials from organic chromophore-containing sol-gel monomers by electric field poling during glass growth, and have been demonstrated as such both with and 10
without impressed bias voltages. The nonlinear response of the doped sol-gel glasses is interrogated through time resolved four wave mixing studies. We determine its morphology that may explain the new optical property. When a laser beam goes through a solid media, the density wave is usually linear. Interestingly, the Cro/CrOx-doped glass generates a strong ‘acoustic response’ due to high grating effect and high photo acoustic diffraction efficiency arisen from alkylene-bridged chemical structure; the arranged structure shown in alkylene-bridged glassy media produces acoustically modulated diffraction.
Figure 1. Sol-gel copolymerization of two monomers. The aryl chromium complex undergoes decomposition to Cro/CrOx under two different polymerization conditions.
Results and Discussions The morphology of the doped sol-gel glass was determined by TEM (Figure 2). The TEM image reveals substantial regions of dark contrast. Electron diffraction analyses of these dark regions indicate a chromium phase in highly organized domains with periodicity sustained over substantial distances; multiple sets of diffraction near the center of the beam (pointed with arrows in Figure 3) corresponding to the dark nanofringes observed in the TEM image.
Figure 2. TEM image of a Cro/CrOx-doped gla
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