Abstract

In recent years the intersubband relaxation in multiple quantum well structures has been investigated by various techniques, in thin quantum wells, in which the subband separation is larger than the phonon energy, the relaxation is dominated by electron-polar-LO-phonon interaction. However, in modulation-doped structures time constants were observed that are longer than the relaxation times estimated from elect roil-phonon interaction.¹ From a theoretical point of view this behavior was explained by a transient transfer of electrons to the barrier potential minima, which delays the relaxation process^.2,3 So far there was no experimental proof for such a transfer process.

© 1997 Optical Society of America