Femtosecond spectroscom of carrier relaxation dynamics in type IICdSe/CdTe tetrapod heteronanostructures

被引：147

作者：

Peng, P ^{[1
]}

Milliron, DJ ^{[1
]}

Hughes, SM ^{[1
]}

Johnson, JC ^{[1
]}

Alivisatos, AP ^{[1
]}

Saykally, RJ ^{[1
]}

机构：

[1] Univ Calif Berkeley, Dept Chem, Berkeley, CA 94720 USA

来源：

NANO LETTERS | 2005年 / 5卷 / 09期

关键词：

D O I：

10.1021/nl0511667

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

Branched nanocrystal heterostructures synthesized from CdSe and CdTe exhibit a type 11 band structure alignment that induces separation of charge upon photoexcitation and localizes carriers to different regions of the tetrahedral geometry. The dynamics of carrier relaxation examined with femtosecond pump-probe spectroscopy showed heterostructures having rise times and biexponential decays longer than those of nanorods with similar dimensions. This is attributed to weaker interactions with surface states and nonradiative relaxation channels afforded by the type II alignment.

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页码：1809 / 1813

页数：5

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