Double quantum well in a semiconductor microcavity: Three-oscillator model and ultrafast radiative decay

A complete study of excitons in double quantum wells embedded in a semiconductor microcavity is presented. In the strong coupling regime we predict the possibility of observing three peaks in optical spectra when the two quantum well excitons have different resonance energies, and discuss the best structure parameters for observing this phenomenon. In the weak coupling regime we show that a radiative lifetime as short as ≊100 fs can be obtained by taking advantage of the coherence between the wells in addition to the microcavity effect. This ultrashort radiative lifetime is shown to be observable even in the presence of disorder.