Abstract

According to the usual understanding, femtosecond pulses which propagate through an inverted semiconductor are amplified if the frequency spectrum of the pulse is entirely engulfed in the gain region of the semiconductor spectrum (see Fig. 1). in contrast to this standard situation, we predict that high intensity pulses might actually be absorbed by the medium. For intermediate intensities we show that the regular amplification and the high-intensity absorption mechanism can combine in such a way that practically lossless propagation is possible, which bears resemblance to solitonlike propagation.

© 1993 Optical Society of America