Theoretical treatment of intense laser fields influence on the femtosecond time-resolved photoelectron spectrum of RbI molecule

The effect of laser fields on the RbI interaction potentials is obtained by the calculation of time-resolved photoelectron spectrum (TRPES) using the time-dependent wave-packet method. Both the normal three-photon ionization process and auto-ionization process are involved in the simulation. This complicated system which involves two ionization continua is successfully treated with a five-state model. The calculated results show not only that the crossings between excited states play important roles during the multiphoton ionization pump-probe process, but also that the intense laser field will change the position of relevant curves, and then influence the shape of the TRPES and ion signal.