Controllability of the wavefunction localization in an asymmetrical bi-periodic GaAs/AlAs superlattice

Electroabsorption properties of a novel asymmetric double-well superlattice are studied experimentally and theoretically. Room temperature photocurrent spectra show an enhanced level anticrossing with energy splitting as large as 80 meV and a distinct blue shift of the optical absorption edge due to suppressed indirect Stark-ladder transitions. By using the transfer matrix method, we show that these electro-optical properties are caused by the wavefunction localization which is well-controlled by the well width asymmetry and the barrier sequence bi-periodicity. (C) 1998 Elsevier Science B.V. All rights reserved.