title: 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.
authors: School of Mechanical Engineering and Birck Nanotechnology Center, Purdue University, West Lafayette, IN 47906, USA.
authors: Bryan T
authors: BT
authors: Spann
authors: Liangliang
authors: L
authors: Chen
authors: Xiulin
authors: X
authors: Ruan
authors: Xianfan
authors: X
authors: Xu
mesh_terms: D019187:Cadmium Compounds / Q000737:chemistry*; D053758:Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology / Q000379:methods*; D010316:Particle Size; D045663:Quantum Dots; D018036:Selenium Compounds / Q000737:chemistry*; D013057:Spectrum Analysis / Q000379:methods*
chemical_list: D019187:Cadmium Compounds; D018036:Selenium Compounds; C058667:cadmium selenide