引用本文:
【打印本页】   【HTML】   【下载PDF全文】   View/Add Comment  【EndNote】   【RefMan】   【BibTex】
←前一篇|后一篇→ 过刊浏览    高级检索
本文已被:浏览 2203次   下载 1705 本文二维码信息
码上扫一扫!
分享到: 微信 更多
Ultrafast Carrier Dynamics in CdSe/CdS/ZnS Quantum Dots
Guan-xin Yao1,2, Zai-xi Fu1, Xian-yi Zhang2, Xian-feng Zheng2, Xue-han Ji2, Zhi-feng Cui*1,2, Hong Zhang*3
1.Anhui Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Hefei 230031, China;2.Institute of Atomic and Molecular Physics, Anhui Normal University, Wuhu 241000, China;3.Van't Hoff Institute for Molecular Sciences, University of Amsterdam, Nieuwe Achtergracht 166, 1018 WV Amsterdam, Netherlands
Abstract:
The intra- and inter-band relaxation dynamics of CdSe/CdS/ZnS core/shell/shell quantum dots are investigated with the aid of time-resolved nonlinear transmission spectra which are obtained using femtosecond pump-probe technique. By selectively exciting the core and shell carrier, the dynamics are studied in detail. Carrier relaxation is found faster in the conduction band of the CdS shell (about 130 fs) than that in the conduction band of the CdSe core (about 400 fs). From the experiments it is distinctly demonstrated the existence of the defect states in the interface between the CdSe core and the CdS shell, indicating that ultrafast spectroscopy might be a suitable tool in studying interface and surface morphology properties in nanosystems.
Key words:  CdSe/CdS/ZnS quantum dot, Femtosecond pump-probe technique, Ultrafast carrier dynamics, Transient transmission spectrum
FundProject:
CdSe/CdS/ZnS 量子点体系中的超快载流子动力学
姚关心1,2, 伏再喜1, 张先燚2, 郑贤锋2, 季学韩2, 崔执凤*1,2, 张宏*3
1.中国科学院安徽光学精密机械研究所,合肥230031;2.安徽师范大学原子与分子物理研究所,芜湖241000;3.荷兰阿姆斯特丹大学分子科学院,阿姆斯特丹166-1018)
摘要:
利用飞秒泵浦探测技术对CdSe/CdS/ZnS量子点体系中的超快载流子动力学过程进行了研究. 通过选择不同波长的泵浦光分别激发样品壳层和核层,研究了载流子在壳层和核层中的超快动力学过程. 实验结果表明,载流子在CdS壳层导带中弛豫过程非常迅速(约130 fs),时间明显短于载流子在CdSe核层导带中的弛豫时间(约400 fs). 实验中也发现在CdS壳层和CdSe核层的分界面存在一定量的缺陷态.
关键词:  CdSe/CdS/ZnS,飞秒泵浦探测技术,超快载流子动力学,瞬态透射谱
DOI:10.1088/1674-0068/24/06/640-646
分类号: