Enhanced Exciton–Phonon Coupling in Spherical GaAs Nanocrystals Studied by Selective Excitation Spectroscopy
نویسنده
چکیده
Phonon-assisted exciton transitions in spherical GaAs nanocrystals embedded in SiO2 matrices have been studied by means of selective excitation spectroscopy. The optical and acoustic phononassisted optical transitions appear in the photoluminescence excitation, photoluminescence linenarrowing, and photoluminescence hole-burning spectra at low temperatures. Both direct (zerophonon) and phonon-assisted recombination of excitons determine the luminescence properties of GaAs nanocrystals. The coupling between excitons and phonons in spherical GaAs nanocrystals is discussed.
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