Defect-induced Photoluminescence from Dark Excitonic States in Individual Single-Walled Carbon Nanotubes

被引：75

作者：

Harutyunyan, Hayk ^{[1
,2
]}

Gokus, Tobias ^{[3
,4
]}

Green, Alexander A. ^{[5
]}

Hersam, Mark C. ^{[5
]}

Allegrini, Maria ^{[1
,2
]}

Hartschuh, Achim ^{[3
,4
]}

机构：

[1] Univ Pisa, Dipartimento Fis E Fermi, I-56127 Pisa, Italy

[2] CNISM, I-56127 Pisa, Italy

[3] Univ Munich, Dept Chem & Biochem, D-81377 Munich, Germany

[4] CeNS, D-81377 Munich, Germany

[5] Northwestern Univ, Dept Chem, Dept Mat Sci & Engn, Evanston, IL 60208 USA

来源：

NANO LETTERS | 2009年 / 9卷 / 05期

基金：

美国国家科学基金会;

关键词：

DYNAMICS; ATOMS;

D O I：

10.1021/nl9002798

中图分类号：

O6 [化学];

学科分类号：

0703 ;

摘要：

We show that new low-energy photoluminescence (PL) bands can be created in the spectra of semiconducting single-walled carbon nanotubes by intense pulsed excitation. The new bands are attributed to PL from different nominally dark excitons that are "brightened" because of a defect-induced mixing of states with different parity and/or spin. Time-resolved PL studies on single nanotubes reveal a significant reduction of the bright exciton lifetime upon brightening of the dark excitons. The lowest-energy dark state has longer lifetimes and is not in thermal equilibrium with the bright state.

引用

页码：2010 / 2014

页数：5

共 38 条

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