Rabi oscillations in realistic superlattice with finite Bloch bands

We investigate the dynamical processes taking place in nanodevices by high- frequency dc-ac fields. We found that Rabi oscillations between minibands a re clearly identified under theoretical resonant conditions derived by an i deal two-band superlattice model, the resonant conditions have broadened, a nd the amount of broadening is about four times of the Rabi oscillation fre quency. We also want to elucidate the role of different mechanisms that cou ld lead to loss of quantum coherence. Our results show how the dephasing ef fects of disorder of interface roughness and doping fluctuation that after some periods destroy coherent oscillations, such as Rabi oscillations, can be reduced dramatically if we apply a bias static electric field to the sup erlattice system. The doping fluctuation dephasing effect is much stronger than that of interface roughness in the coherent process of realistic super lattices.