Abstract

In recent experiments, short-pulse excitation of undoped semiconductor double quantum wells¹ and superlattices² in an electric field has been used to form excitonic wavepackets from a coherent superposition of the underlying stationary states. We examine the wavepacket evolution, including the Coulomb interaction between the electrons and holes, as well as the effects of the terahertz radiation field resulting from the wavepacket oscillation. It has been suggested that in superlattices, the time evolution of these wavepackets represents Bloch oscillations. We investigate the evolution of such wavepackets as a function of the excitation parameters and discuss the degree to which Bloch oscillations can be achieved.

© 1993 Optical Society of America