Time-resolved photodetached spectroscopy of H− in electric field near an elastic surface

The advances in femtosecond laser techniques facilitate the investigation of ultrafast electron dynamics on surfaces directly in time domain. The time-resolved spectroscopy of negative hydrogen ion in electric field near an elastic surface is investigated in the framework of semiclassical theory. We analyze the autocorrelation function and its dependence on the laser pulse width and external field strength. When the applied pulse width is very narrow, the reviving peaks in the time-resolved spectrum can be attributed to the closed orbits of electrons. With the increase of pulse width, the adjacent peaks interference mutually and finally merge. Furthermore, the number and amplitude of peaks in the time-resolved spectrum increases obviously with the increasing field strength.