Photoluminescence spectral switching of single CdSe/ZnS colloidal nanocrystals in poly(methyl methacrylate)
نویسندگان
چکیده
We investigated emission from single CdSe nanocrystals in poly methyl methacrylate . A fraction of the nanocrystals exhibited switching between two energy states which had similar total intensities but distinctly different spectra. We found that the characteristic frequency of this spectral shift increased with the pump power. By using the dynamic shift in the spectral position of emission peaks, we were able to correlate peaks from the same nanocrystal. The measured correlation is consistent with assignment of low energy lines to phonon replicas.
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