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A u.v. fiber‐coupled resonant laser‐ablation chamber

This paper describes the characterization of a u.v. transmitting fibre which forms the basis of a novel type of resonant ablation vacuum chamber. Resonant Laser Ablation (RLA) is a relatively new surface analysis technique which has been used to study impurity concentrations at relatively low laser fluences. These results have indicated that if a moderately focused laser resonant wavelength laser beam is directed at a grazing angle of incidence to the target surface, the resulting ion yield may be enhanced by two orders of magnitude or more. RLA is therefore ideally suited to surface analysis. However, it is known that any movement of the beam relative to the surface of the target results in poor reproducibility and it is for this reason that a large core all‐silica u.v. transmitting fibre has been chosen to couple the laser beam to the vacuum chamber. An additional advantage of the fibre is that the laser beam is confined within it thereby rendering the system intrinsically safe. Because of its underlyin...