Spectroscopic imaging of nanoparticles in laser ablation plume by redecomposition and laser-induced fluorescence detection

We propose and demonstrate an imaging technique to observe clusters formed in a laser ablation plume, which are difficult to be detected by conventional laser-induced fluorescence (LIF) and ultraviolet Rayleigh scattering techniques. The clusters were decomposed by the irradiation of another laser beam, and the disintegrated atoms were visualized by a two-dimensional LIF technique. This technique was applied to visualize the formation process of clusters in a laser ablation plume. Based on this imaging diagnostics, the onset time of the clustering in the plume is discussed. (C) 2000 American Institute of Physics. [S0003-6951(00)03541-5].