The pulse reshaping of femtosecond laser pulses tuned to Rydberg transitions of strontium vapor is observed experimentally. We show theoretically that their shape closely reflects the dynamics of Rydberg wave packets induced by the pulses. The decay and compression of Rydberg wave packets excited by both Fourier limited and chirped fs pulses is presented.

doi:10.1103/PhysRevLett.79.4774