Three-photon near-threshold photoionization dynamics of i300ctane

摘要

The electron survival probability following three-photon(9.3 eV total)near-threshold photoionization of neat i300ctane is measured with sub-50 fs time resolution.The measured dynamics are nonexponential in time and are well described by a diffusion-controlled electron-cation recombination model.Excitation-power-dependent studies indicate that the unperturbed three-photon threshold ionization is only observed for pump irradiance below 0.5 TW/cm~2.At excitation fields above this level,the signal is no longer cubic in the excitation irradiance,and the observed electron survival probability dramatically changes,decaying as a single exponential in time.