Enhancement of intersubband transition energies in GaAs quantum wells by Si delta doping of high concentration

Intersubband light absorption measurements have been performed on a series of GaAs/AlAs quantum wells with heavy delta doping of Si atoms in the range 9.0×1011–6.5×1012 cm−2. The increase of intersubband transition energy by as much as 38 meV has been observed, and attributed to the deepening of the V-shaped potential by the Si layer and to the depolarization effects.