Field dependence of Autler-Townes splitting in pump/probe setup

Abstract

We theoretically investigate the Autler-Townes (AT) splitting in the photoelectron spectra of threelevel ladder K2 molecule driven by a pump-probe pulse via employing the time-dependent wave packet approach. The effect of the pump/probe laser intensity and wavelength on AT splitting is detailed studied. The magnitude of AT splitting increases with increasing the pump laser intensity, but does not vary with probe intensity. The double splitting with asymmetric profiles arises due to the nonresonant excitation. The double structure is transformed into one peak progressively as the pump is detuned from the resonance wavelength, which can be explained in terms of the asymmetric excitation/population of dressed states. The splitting between AT doublet changes with pump wavelength, but does not change with probe wavelength. The double peaks shift to lower energy with the different shift with increasing pump wavelength, but with the same shift with probe wavelength.