Energy levels and far-infrared absorption of multi-stacked dots

We present a theoretical study of electron states and oscillator strengths for the intra-conduction band transitions in single dots or stacked dot arrays. Single dots display virtually no bound-to-bound transitions for light polarized parallel to the growth axis while the bound-to-bound transitions almost exhaust the oscillator strength for light polarized parallel to the basal plane of the dot. On the contrary, multi-stacked (coupled) dots display significant absorption probability linked to bound-to-bound transitions for both polarizations. (C) 2001 Elsevier Science B.V. All rights reserved.