ABSTRACT
We have investigated interactions between the quantized states in a single quantum well (SQW) embedded in the center of a superlattice (SL) and the Wannier-Stark ladder states in the superiattice by low temperature photocurrent (PC) spectroscopy. It is found that the PC spectral features related with the ground heavyhole and light-hole excitonic states in the SQW exhibit very clear and drastic changes of the transition energies and their oscillator strengths as a function of electric field due to the various resonant couplings both in the conduction and valence subbands. Based on transfer matrix calculations of the eigen-energies and wavefunction overlap integrals, observed anticrossings and delocalization phenomena are rigorously explained.
