Effects of the pulse area and pulse number on the population dynamics of atoms interacting with a train of ultrashort pulses

We theoretically investigate the effects of the pulse area and the pulse number in a train of ultrashort pulses with an ultrahigh repetition rate in terms of the population dynamics. Because of the interpulse interference the upper state population exhibits an oscillatory behavior as a function of the laser detuning. The pulse area and the pulse number significantly affect the periodic structure of population oscillation.