Interband absorption cross-section and Rabi oscillations in semiconductors

A numerical method is described that allows to find differential interband absorption cross-section of infrared (IR) radiation in solids in the case of complex energy bands. The method is based on observation of carrier population oscillations between two selected energy bands. Absorption due to hole intervalence transitions in p-InP, when both the nonparabolicity and the warping of heavy, light and spin–orbit split-off valence bands is taken into account, is presented as an illustration of the method. The method allows us to calculate the resonance shift and change of the cross-section at high IR light intensities.