Can someone provide me any references which report the relative magnitude of the slow decaying component to fast decaying component A2/A1 in a biexponential decay function of the time-resolved photoluminescence measurement for InGaAs/GaAs quantum wells? I would like to know the ratio A2/A1. The quantum wells could be based on homoepitaxy (on GaAs substrates) or heteroepitaxy (e.g. on Si substrates).