Energy relaxation in CdSe nanocrystals: the effects of morphology and film preparation.

نویسندگان

  • Bryan T Spann
  • Liangliang Chen
  • Xiulin Ruan
  • Xianfan Xu
چکیده

Ultrafast time-resolved absorption spectroscopy is used to investigate exciton dynamics in CdSe nanocrystal films. The effects of morphology, quantum-dot versus quantum-rod, and preparation of nanocrystals in a thin film form are investigated. The measurements revealed longer intraband exciton relaxation in quantum-rods than in quantum-dots. The slowed relaxation in quantum-rods is due to mitigation of the Auger-relaxation mechanism from elongating the nanocrystal. In addition, the nanocrystal thin film showed long-lived confined acoustic phonons corresponding to the ellipsoidal breathing mode, contrary to others work on colloidal systems of CdSe nanocrystals.

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عنوان ژورنال:
  • Optics express

دوره 21 Suppl 1  شماره 

صفحات  -

تاریخ انتشار 2013