ULTRAFAST PHOTOEXCITATION AND COHERENT DYNAMICS OF ELECTRONS IN TRIPLE TUNNEL-COUPLED QUANTUM-WELLS

Coherent dynamics of electrons in the triple tunnel-coupled quantum we lls after an ultrafast optical excitation is studied. In a collisionle ss approximation, we consider temporal evolution of the electron distr ibution for different parameters of structure and pulse duration. Due to mixing of the tunneling frequencies under the three-level tunneling resonance condition, transient evolution of the dipole moment demonst rates different kinds of behavior: harmonic oscillations, beats, and n onperiodic oscillations. (C) 1996 American Institute of Physics.