Electron photodetachment by short laser pulse

Expressions are derived for calculations of the total probabilities and electron spectra for the photodetachment of electrons from negative ions with filled valence s shells by ultrashort laser pulses. Particular calculations have been performed for two negative ions (H⁻ and Li⁻) and titanium-sapphire laser pulses with a carrier wavelength of 0.8 μm and a duration of 4 fs. It is shown that measurements of the electron energy spectra allow either the emission spectrum to be determines for the known cross-section of photodetachment or a dispersion curve of the electron photodetachment cross section to be constructed for the given spectrum of laser pulses. In addition, these measurements provide a tool for the exact determination of electron binding energies.