Linear optical glasses

The ratio Db/Da is a so-called relative sensitivity factor D. This ratio is mostly determined by one element, e. g. the element for insulating samples, silicon, which is one of the main components of glasses. By use of the equation that the sum of the concentrations of all elements is equal to unity, the bulk concentrations can be determined directly from the measured intensities and the known D-factors, if all components of the sample are known. The linearity of the detected intensity and the flux of the sputtered neutrals in IBSCA and SNMS has been demonstrated for silicate glasses [4.253]. For SNMS the lower matrix dependence has been shown for a variety of samples [4.263]. Comparison of normalized SNMS and IBSCA signals for Na and Pb as prominent components of optical glasses shows that a fairly good linear dependence exists (Fig. 4.49). 

The unique features of chalcogenide glasses (Chap. 6), such as quasi-stability, photoconductivity, infrared transparency, non-linear optical properties, and ionic... 

An intense femtosecond laser spectroscopy-based research focusing on the fast relaxation processes of excited electrons in nanoparticles has started in the past decade. The electron dynamics and non-linear optical properties of nanoparticles in colloidal solutions [1], thin films [2] and glasses [3] have been studied in the femto- and picosecond time scales. Most work has been done with noble metal nanoparticles Au, Ag and Cu, providing information about the electron-electron and electron-phonon coupling [4] or coherent phenomenon [5], A large surface-to-volume ratio of the particle gives a possibility to investigate the surface/interface processes. 

The non-linear optical properties of a glass depend not only on the occupied electronic states but also on the unoccupied orbitals, demanding a theory which can treat both sets of states. The unoccupied molecular orbitals are typically diffuse in nature, a "local excitation" involving atomic orbitals of a considerable group of neighboring ions. 

Danyushevskii E. E., Principles of Optical Glass Linear Annealing (in Russian), Oborongiz. Moscow, 1959. 

M, Mortier, A, Bensalah, G, Dantelle, G, Patriarche, D, Vivien, Rare-earth doped oxyfluoride glass-ceramics and fluoride ceramics Sintesis and optical properties. Opt. Mat., 29, 1263-1270 (2005), Patterning of non-linear optical crystals in glass by laser-induced crystallization, J. Am. Ceram. Soc. 90, 699-705 (2007),... 

Materials with appreciable values of j8 leading to frequency doubling are called second-order Non Linear Optics (NLO) materials. Such materials lack a center of symmetry since the magnitude of the induced M is different for +E and -E. Molecules of this sort typically have donor and acceptor groups on opposite sides of the molecule making it easier for electrons to move in one direction than the other. Of course, to be active, the molecule must be oriented. With polymers, this can be accomplished by poling where the material is subjected to an electric field above its glass temperature and been quenched with the field on so as to freeze the molecule in their ordered state. 

Molecules 19-22 are model systems for a related project, which aims to incorporate D-a-A systems into LB-film-forming diacetylenes, which may be polymerized in situ on the film balance, for the purpose of preparing new systems with promise as non-linear optical devices. Interestingly, 19-22 form Z-type multilayers on a glass substrate (the film subphase is held at 5° C but the slide is at room temperature). An attempt was made to see whether any second harmonic signals could be detected from Z multilayers of 21, but the result was negative [47]. 

Linear optical sensors measure the actuator movement in the data acquisition process. To do this, the sensor scanning head is fixed to the rod actuator and the sensor glass scale is fixed to the actuator casing. 

Harold Ackler, Lawrence Livermore National Laboratory, got a MS degree in Materials Science and Engineering at the University of California in Berkeley, and a Ph.D. degree in Ceramics at the Massachusetts Institute of Technology. His research, while at Bell Laboratories, Lucent Technologies, has focused on the processing of optical fiber preforms via sol-gel methods, planar photonic devices, and glasses with non-linear optical properties. 

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