Energy relaxation in CdSe nanocrystals: the effects of morphology and film preparation
Abstract
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. (C) 2012 Optical Society of America
Keywords
SEMICONDUCTOR QUANTUM DOTS; MULTIPLE EXCITON GENERATION; SOLAR-CELLS; DYNAMICS; NANORODS
DOI
10.1364/OE.21.000A15
Citation
Optics Express Vol. 21, Issue S1, pp. A15-A22 (2013)
Date of this Version
1-14-2013
Recommended Citation
Spann, Bryan T.; Chen, Liangliang; Ruan, Xiulin; and Xu, Xianfan, "Energy relaxation in CdSe nanocrystals: the effects of morphology and film preparation" (2013). Birck and NCN Publications. Paper 1328.
http://dx.doi.org/10.1364/OE.21.000A15