Terahertz electric polarizability of excitons in PbSe and CdSe quantum dots

被引：25

作者：

Dakovski, Georgi L. ^{[1
]}

Lan, Song ^{[1
]}

Xia, Chen ^{[1
]}

Shan, Jie ^{[1
]}

机构：

[1] Case Western Reserve Univ, Dept Phys, Cleveland, OH 44106 USA

来源：

JOURNAL OF PHYSICAL CHEMISTRY C | 2007年 / 111卷 / 16期

关键词：

D O I：

10.1021/jp069026o

中图分类号：

O64 [物理化学（理论化学）、化学物理学];

学科分类号：

070304 ; 081704 ;

摘要：

Terahertz time-domain spectroscopy was employed to investigate photogenerated excitons in PbSe and CdSe quantum dots (QD) of radii less than their exciton Bohr radius. The exciton response was found to be "atom"-like and rise with increasing the carrier effective mass. Excitons in CdSe were found to be about two times more polarizable than those in PbSe QDs of equal size. These experimental findings including both the magnitude of the exciton polarizability and its variation with the QD radius were well described by an effective mass model with multiband structures of the QD materials.

引用

页码：5904 / 5908

页数：5

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