Abstract

Femtosecond spectroscopy of semiconductors has identified a regime of coherent response in which the optical polarization of the material and the electric field of the optical pulse couple in a phase coherent way. Most experiments have concentrated on excitonic polarizations with picosecond dephasing times, and phenomena like wave packet propagation and quantum beats have been observed. Much less is known on nonlinear polarizations in the band-to-band continuum showing a much faster dephasing. In this paper, we report the first observation of heavy-light hole (HII-LH) quantum beats in the band-to-band continuum of bulk GaAs.

© 1997 Optical Society of America