Phonons and exciton recombination in CdSe/ZnSe self-assembled quantum dots

We report resonant photoluminescence from CdSe/ZnSe self-assembled quantum dots. When CdSe quantum dots are resonantly excited, excitonic sharp micro- photoluminescence peaks originating from individual quantum dots are strong ly enhanced in the region corresponding to optical phonon energies below th e excitation. The phonons active in this process are identified as the long itudinal optical (LO) phonons from the CdSe dots, as the interface phonons, and tentatively as the LO phonons from the two-dimensional-like precursor layers. These observations suggest that exciton recombination via phonons i s a major relaxation process under resonant excitation. (C) 2000 American I nstitute of Physics. [S0003-6951(00)02938-7].