The recent rapid advances in the field of laser ablation have led to an important new tool for both material synthesis and material processing. Experiments in our laboratory have served as examples of both types of contributions from this new technique. The kinetic differences of growth between standard solid state synthesis and in situ growth by laser ablation have allowed the substitution of Ce, Tb and Th for Y in Y1Ba2Cu3O7 for the first time. The effects of substitution for Y on the material Tc is discussed within the framework of the existing models for the Pr system. We suggest that localization of the holes by trapping may provide a suitable mechanism to account for the observed properties of the Pr and Ce substituted compounds. As an example of new material processing, polytetrafluoroethylene (PTFE) films were deposited by the laser ablation of a bulk PTFE target using the 4th harmonic, at 266 nm, of a Nd-YAG laser. The films are found to be stoichiometric with bulk- like optical properties. We propose a model which suggests that UV absorption onsets the pyrolitic decomposition of PTFE leading to monomer as the main ablation product. The monomer, ejected from the target at high velocity, subsequently re-polymerizes on the substrate.
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