Theoretical investigation of pump–probe photoelectron spectroscopy on KLi

Based on the time-dependent quantum wave packet method, the ionization dynamics of the KLi molecule are theoretically simulated using the pump–probe technique. The Autler–Townes splitting phenomenon of photoelectron spectroscopy is analyzed by changing the laser pulse width, the intensity of the probe laser pulse, and the delay time between the pump and probe pulses. It has been found that the height difference between the splitting peaks becomes larger as the width of the pump pulse increases under the resonant condition. Furthermore, the probe laser with large pulse width has little effect on the peak height difference compared with the pump pulse, but it results in multi-splitting of the photoelectron spectroscopy. Meanwhile, the effect of delay time on the splitting peaks in photoelectron spectroscopy is investigated. (paper)