Dynamics of inter- and intra-growth island exciton transfer in GaAs single quantum wells under direct picosecond optical excitation

摘要: Abstract The low temperature transfer dynamics of localized excitons in 19 to 22 monolayer-wide GaAs single quantum well (SQW) growth islands is investigated by time-resolved photoluminescence (PL) experiments. Under direct photogeneration the well, we find that SQW emissions exhibit two distinct exponential decay rates (fast and slow) which are strongly dependent on emission energy. A consistent model proposed explain observed time behaviors terms inter- intra-growth island exciton wider intrinsic defect sites within each island, respectively. dramatic change disappears at higher temperatures when detrapping processes operative.