Shortcomings of laser ablation

Some of the problems encountered in using the LA technique arise from so-called elemental fractionation, a non-sample related change in the analyte response during the ablation process. This effect has been observed to some extent with all types of lasers, but other variables including energy density, focal point and the crater diameter-to-depth ratio also appear to exert a strong influence [9-13,39,51]. 

A number of specific approaches to minimizing elemental fractionation have been developed [11,14,54,57,58], It remains impossible to pinpoint the source of fractionation  

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