| The interaction of femtosecond laser radiation with matter, especially clusters, has blossomed in recent years due to advances in laser technology. One aspect of this interaction is Coulomb explosion. This effect occurs when the repulsive energy of similar charges, known as Coulomb repulsion, overcomes the cluster's total cohesive energy, causing the cluster to disintegrate into charged fragments. In this study, the interactions of methyl iodide clusters formed in a supersonic expansion using argon and helium as carrier gases have been studied at 795 and 397 nm using a Ti:Sapphire femtosecond laser. The resulting atomic and cluster ions were analyzed in a reflectron time-of-flight mass spectrometer.; The focus of these studies was the elucidation of the effects of carrier gas and laser wavelength on the laser-cluster interactions leading to Coulomb explosion. To achieve these goals, the effects of different carrier gases (argon and helium), laser power, cluster distribution and the resulting Coulomb explosion energies were examined. A secondary consideration was to examine the experimental results with regard to the Coherent Electron Motion and Ionization Ignition models. This comparison should lead to at least a partial explanation of the mechanism behind the Coulomb explosion process under study. |
