Direct laser-induced problems

One way to effect a rapid change in the interfacial temperature is by impinging a pulsed laser beam directly onto the electrode [66 71] we will refer to this method as the direct laser-induced temperature-jump method (DLIT). DLIT has several fundamental problems ... 

In contrast, laser irradiation has been shown to provide a potential solution to this problem. Laser-induced removal of the contaminants can be effected either via direct absorption of the laser light by the particles and/or the substrate ( dry laser cleaning ) or via the prior application of a liquid film ( steam laser cleaning ) [3]. The particle removal process can be evaluated either directly, by post-treatment optical or scanning electron microscopic examination of the sample, or indirectly via the scattering by the par-... 

In both of these two cases, the heat of evaporation is greater than the energy of the thermal degradation of the molecules. Therefore, methods omitting evaporation prior to ionization had to be looked for. Several attempts were made to overcome this problem . Today, the most promising methods using ionization of the sample in the solid state directly from a probe surface are field desorption (FD), desorption chemical ionization (DCI), Cf-plasma desorption technique, and laser-induced desorption technique. 

Since in densely populated industrial areas air and water pollution has become a serious problem, the study of pollutants and their reactions with natural components of our environment is urgently needed [15.75]. Various techniques of laser spectroscopy have been successfully employed in atmospheric and environmental research direct absorption measurements, laser-induced fluorescence techniques, photoacoustic detection, spontaneous Raman scattering and CARS (Chap. 8), resonant two-photon ionization, and many more of the sensitive detection techniques discussed in Chap. 6 can be applied to various environmental problems. This section illustrates the potential of laser spectroscopy in this field by some examples. 

The goal of this book is to present in a coherent way the problems of the laser control of matter at the atomic-molecular level, namely, control of the velocity distribution of atoms and molecules (saturation Doppler-free spectroscopy) control of the absolute velocity of atoms (laser cooling) control of the orientation, position, and direction of motion of atoms (laser trapping of atoms, and atom optics) control of the coherent behavior of ultracold (quantum) gases laser-induced photoassociation of cold atoms, photoselective ionization of atoms photoselective multiphoton dissociation of simple and polyatomic molecules (vibrationally or electronically excited) multiphoton photoionization and mass spectrometry of molecules and femtosecond coherent control of the photoionization of atoms and photodissociation of molecules. 

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