Intersubband absorption of TE and TM waves in p-type semiconductor superlattice including the effects of continuum states

We present theoretical results for the absorption coefficients for both TE and TM waves due to intersubband transitions within the valence subbands of a p-type superlattice. Both the bound and continuum states are included in our calculation. The continuum states are discretized by applying a periodic boundary condition. Numerical results are illustrated for different well and barrier widths. The results show that the intersubband transitions among the bound states result in sharp resonance absorption while the intersubband transitions between bound states and continuum states give a broad maximum at a photon energy larger than the barrier height. The TE and TM absorption coefficients are comparable in magnitude. Our theoretical results are in agreement with recent experimental observations on bound states to continuum states transitions