Transparency, laser-induced

S.M. Sadeghi, J. Meyer, H. Rastegar, Laser-induced transparency and dark-line effects caused by three-wave mixing in atomic systems, Phys. Rev. A 56 (1997) 3097. 

Fig. 6.4. Statistical confidence level associated with the electric events synchronized with the laser pulses during a thunderstorm. The color scale is transparent below 98% (i.e., for error risks above 2%), leaving the topographical background uncovered. Arrowhead location of the laser-induced plasma channel Arrow tail laser emitter. Topographic background courtesy of US Geological Survey [31]...

The discovery of self-focussing of intense laser beams 318 ) and the phenomena of self-induced transparency 318b) have stimulated a whole new class of experimental investigations which give information about the transient interaction between light and matter 318c)... 

Coppeta et al. [10] made slurry film measurements during using laser-induced fluorescence. By addition of a fluorescent dye to the polishing slurry film thickness was experimentally from the fluorescence intensity of the lubrication film as measured through a transparent substrate. Film thickness measurements were in good agreement with those of Levert et al. [7,8]. This technique can also be used to study slurry transport across the wafer surface, diameter variation in lubrication film thickness, and slurry mixing effects [11]. 

Scenario associated with electromagnetically induced transparency (i.e., old levels, (levels 2,) and 22), and associated fields). Note that the inset shows excitation to two piratic states, as discussed in the text. Here our levels 2 0), ,), and EZ) are denoted, and 2), respectively. The laser wavelengths are denoted Xp and Xc. (Taken from Fig. [297].)... 

Figure 1. Laser-induced ultrasonic wave excitation and detection using ISLS. Two 100 picosecond infrared pulses converge spatially and temporally within a transparent sample medium. The time-dependant intensity or strength of the optical transient diffraction grating is monitored by a third frequency doubled pulse which, in the case for relatively low scattering strength, is systematically delayed in time. The time response of stronger gratings can be monitored using a CW laser.

Hamiltonian in an extended space, the direct product of the usual molecular Hilbert space, and the space of periodic functions of f e [0,T]. This extension of the Hilbert space can be made somewhat more transparent by introducing a new time-like variable, to be distinguished from the actual time variable t. This new time variable can be defined through the arbitrary phase of the continuous (periodic) field, as done in Ref. [28, 29]. A variant of the idea is found in the (f, t ) method developed by Peskin and Moiseyev [30] and applied to the photodissociation of HJ [31, 32]. We will continue with the more traditional and simpler formulation of Floquet theory here, as this is sufficient to bring out ideas of laser-induced resonances in the dressed molecule picture. 

The continuous parts of the spectra ("continua") of atomic and molecular systems were traditionally thought of as incoherent sinks that result in "rate-like" processes and irreversible decay. While this view may sometimes be true for confinua whose coupling matrix element varies relatively slowly with energy ("flat" continua), experiments of fhe last two decades have demonstrated coherent behavior in many laser-mediated processes associated with continua. The "dressing" of confinua by light was shown to cause coherent phenomena, such as induced transparency, nonexponential decay and recurrences, and "above-threshold" ionization and dissociation processes, involving optical transitions within continua. 

Detection methods in gel filled capillaries are most commonly UV-absorption and laser induced fiuorescence. Proteins have a high UV-absorbance at k = 200 nm and X = 214 nm. Polyacrylamide gels absorb strongly at k < 230 nm and are, therefore, not suitable for protein analysis. Dextrane or PEG can be used as alternatives, as they are both UV-transparent. The absorption of DNA fragments is usually measured at k = 260 nm (see section 1.3.3.1), for which PA gels are well suited. 

When an intense laser beam is focused inside a transparent medium a laser-induced break-down and plasma can be formed in as short a time as 6 psec. This very fast formation is the result of the very highly nonlinear process of plasma formation. The process is so complex that it remains a major subject of current research. As a result, only a qualitative discussion is presented in this article. 

Y. F. Li, J. F. Sun, X. Y. Zhang, and Y. C. Wang. Laser-induced double-dark resonances and double-transparencies in a four-level system. Optics Communications 2002 Feb l 202(l-3) 97-102. 

Oxides of transition metals, such as niobium, tantalum, or titanium, are suitable as waveguiding layers on optical (grating coupler) waveguides due to their high refractive index and transparency. Therefore, oxide-coated chips are used as sensing devices in technology based on the interaction of a laser-induced evanescent field with analyte constituents adsorbed on or immobilized at the waveguide/ fluid interface. ... 

Phillips HM, Li Y, Bi X, Zhang B (1996) Reactive pulsed laser deposition and laser induced crystallization of SnO transparent conducting thin films. Appl Phys A 63 347-351 Pique A, Auyeung RCY, Stepnowsk JL, Weir DW, Arnold CB, McGiU RA, Chrisey DB (2003) Laser processing of polymer thin films for chemical sensor applications. Surf Coat Technol 163-164 293-299 Randhaw H (1991) Review of plasma-assisted deposition processes. Thin Solid Films 196 329-349 Risti M, Ivanda M, Popovi S, Musi S (2002) Dependence of nanocrystaUine SnO particle size on synthesis route. J Non-Crystal Solids 303 270-280... 

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