Quantization of the biexcitonic continuum states in semiconductor quantum wells by localization

The signature of excitonic localization on the biexcitonic continuum is investigated in GaAs single and multiple quantum wells. With increasing localization, the biexciton binding energy increases, while the biexciton continuum shifts to energies above the exciton resonance. The localization leads to an inhomogeneous broadening of the biexciton binding energy and of the biexciton continuum edge. For localization energies larger that the biexciton binding energy, the oscillator strength of the biexciton continuum is reduced by the quantization of the excitonic states in the localization potential.