OPTICAL PROCESSES IN SEMICONDUCTOR NANOCRYSTALLITES (QUANTUM DOTS)

The results of theoretical and experimental studies of the electronic properties of semiconductor crystallites comparable in size to the de Broglie wavelength of electrons and holes-so-called quantum dots-are a nalyzed and generalized. Attention is devoted mainly to crystallites o f direct-gap II-VI and I-VII compounds. It is shown that nonlinear las er spectroscopy can be effectively employed to separate the properties of individual crystallites in investigations of an ensemble of crysta llites with an unavoidable variance of the particle sizes. The photolu minescence, lasing, and saturation of optical absorption are examined. The multiparticle states and exciton-exciton interactions, phase rela xation mechanisms, and photochemical processes are discussed. (C) 1996 American Institute of Physics.