Effect of the ratio of transition dipole moments on few-cycle pulse propagation

Propagation of a few-cycle laser pulses in a dense V-type three-level atomic medium is investigated based on full-wave Maxwell-Bloch equations by taking the near dipole-dipole (NDD) interaction into account. We find that the ratio,γ,of the transition dipole moments has strong influence on the time evolution and split of the pulse:whenγ≤1,the NDD interaction delays propagation and split of the pulse,and this phenomenon is more obvious when the value ofγis smaller;whenγ=2~(1/2),the NDD interaction accelerates propagation and split of the pulse.