Organic pulse lasers

There have been remarkable advances in the physical organic chemistry of aromatic carbenes in the past five years. The intensive study of these reactive intermediates engendered by the development of high-speed pulsed lasers has rekindled interest in this topic. The capacity to observe these species directly under actual reaction conditions permits examination of details heretofore only wished for. These studies have provided answers for old questions and raised new horizons. 

Organic dye lasers are especially useful for nanosecond absorption spectroscopy since their wavelength can be tuned continuously over a range of several hundred angstroms and their output pulses reach several megawatt at pulsewidths down to 10" sec with mode-locking techniques. 

For their rich potential in various applications described in the previous section, the synthesis and assembly of various ZnO micro and nanostructures have been extensively explored using both gas-phase and solution-based approaches. The most commonly used gas-phase growth approaches for synthesizing ZnO structures at the nanometer and micrometer scale include physical vapor deposition (40, 41), pulsed laser deposition (42), chemical vapor deposition (43), metal-organic chemical vapor deposition (44), vapor-liquid-solid epitaxial mechanisms (24, 28, 29, 45), and epitaxial electrodeposition (46). In solution-based synthesis approaches, growth methods such as hydrothermal decomposition processes (47, 48) and homogeneous precipitation of ZnO in aqueous solutions (49-51) were pursued. 

The theory of thermal aspects of laser desorption has been developed for a substrate surface subjected to pulsed laser irradiation, assuming that the laser intensity has a Gaussian distribution [21], The given surface is covered with the organic layer, which does not absorb the laser energy. However, the heat flux in the substrate that absorbs the energy heats the sample to the same temperature as the substrate. For this case, the laser intensity flux /(r,t) is given by... 

Adachi, H., Hosokawa, Y., Takano, K., Tsunesada, F., Masuhara, H., Yoshimura, M., Mori, Y. and Sasaki, T. (2002) Effect of short pulse laser on organic and protein ... 

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