Hyperspectral Probing of Exciton dynamics and Multiplication in PbSe Nanocrystals

نویسندگان

  • H. Sachs
  • A. Roitblat
  • D. Strasfeld
  • M. G. Bawendi
  • I. Gdor
چکیده

Height time hyperspectral near IR probing providing broad-band coverage is employed on PbSe nanocrystals, uncovering spectral evolution following high energy photo-excitation due to hot exciton relaxation and recombination. Separation of single, double and triple exciton state contributions to these spectra is demonstrated, and the mechanisms underlying the course of spectral evolution are investigated. In addition no sign of MEG was detected in this sample up to a photon energy 3.7 times that of the band gap.

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تاریخ انتشار 2012