Asymmetrical photoelectron angular distributions in ionization of NaK molecules driven by pump-probe femtosecond laser pulses

Abstract

We study the asymmetrical photoelectron angular distribution (PAD) in the ionization of NaK molecules driven by pump–probe femtosecond laser pulses. We find that the carrier-envelope phase (CEP) of laser pulse has a larger effect on molecular orientation and PAD. Different molecular orientations correspond to different PADs. A strong asymmetry mainly results from a larger molecular orientation in the excited state. Uni-direction photoionization may take place by adjusting the CEP of the laser pulse and controlling the molecular orientation in the ground state. Moreover, the duration of the laser pulse also has some influence on the PAD.