Excitonic properties and resonance widths in biased (Ga,In)As-GaAs double quantum wells

We calculate the exciton properties and resonance widths of the charge carriers trapped in (Ga,In)As-GaAs double quantum wells embedded in p-i-n diodes. The calculation is made for both the (001)- and (111)B-oriented structures and evidences the dramatic influence of the built-in piezoelectric field that occurs when the growth axis is (111). We also perform excitation calculations, which show that, when the band lineups are deformed due to the excitonic interaction between particles, the overlap integral of the wave functions increases and so the carriers’ escape time out of the quantum-well diodes increases with respect to the values calculated for the ‘‘empty’’ crystal.