Bound-to-bound intersubband transitions in a δ-doped p-type Si/SixGe1−x/Si quantum well

Abstract
The absorption spectrum in p‐type Si/Si0.6Ge0.4/Si structure with a δ‐doped quantum well grown on Si(001) substrate is calculated using a multiband model. We have generalized the previous treatment of the depolarization effect in n‐type Si to include subband multiplicity, nonparabolicity, and valence band anisotropy. An implicit formula for the effective plasma frequency was used to conveniently include these effects in the calculation. We found that it is necessary to treat the depolarization effect in the complicated couplings among valence bands in order to explain the observed spectrum.