ABSTRACT
Field-free orientation of CO molecule is studied theoretically by combining two dual-color shaped laser pulses with low intensity of THz laser pulse. It is indicated that the molecular orientation can be greatly improved by applying two dual-color shaped laser pulse and lower intensity of THz laser pulse compared with single THz laser pulse. The influence of the electric field amplitude of the two dual-color shaped laser pulses on molecular orientation is discussed. Furthermore, by varying the delay time t d1 between the two dual-color shaped laser pulses as well as the delay time t d between the second dual-color shaped laser pulse and THz laser pulse, the molecular orientation can be changed to some extent. Additionally, it’s also shown that the enhancement or suppression of the molecular orientation can be coherently manipulated by changing the center frequency and the carrier envelope phase of the THz laser pulse.
