期刊
NANO LETTERS
卷 15, 期 8, 页码 4985-4992出版社
AMER CHEMICAL SOC
DOI: 10.1021/acs.nanolett.5b00966
关键词
Two-photon absorption; CdSe; nanoplatelets; nanorods; quantum dots; local field
类别
资金
- DFG [Wo 477/32, AC 290/1]
- CHEMREAGENTS program
- [X13M-017]
We report a comprehensive study on the two-photon absorption cross sections of colloidal CdSe nano-platelets, -rods, and -dots of different sizes by the means of z-scan and two-photon excitation spectroscopy. Platelets combine large particle volumes with ultra strong confinement. In contrast to weakly confined nanocrystals, the TPA cross sections of CdSe nanoplatelets scale superlinearly with volume (V-similar to 2) and show ten times more efficient two-photon absorption than nanorods or dots. This unexpectedly strong shape dependence goes well beyond the effect of local fields. The larger the particles' aspect ratio, the greater is the confinement related electronic contribution to the increased two-photon absorption. Both electronic confinement and local field effects favor the platelets and make them unique two-photon absorbers with outstanding cross sections of up to 10(7) GM, the largest ever reported for (colloidal) semiconductor nanocrystals and ideally suited for two-photon imaging and nonlinear optoelectronics. The obtained results are confirmed by two independent techniques as well as a new self-referencing method.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据