Spin spectroscopy of dark excitons in CdSe quantum dots to 60 T

被引：66

作者：

Johnston-Halperin, E ^{[1
]}

Awschalom, DD

Crooker, SA

Efros, AL

Rosen, M

Peng, X

Alivisatos, AP

机构：

[1] Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA

[2] Natl High Magnet Field Lab, Los Alamos, NM 87545 USA

[3] USN, Res Lab, Nanostruct Opt Sect, Washington, DC 20375 USA

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

来源：

PHYSICAL REVIEW B | 2001年 / 63卷 / 20期

关键词：

D O I：

10.1103/PhysRevB.63.205309

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

Polarization-resolved magnetophotoluminescence spectroscopy is used to study exciton spin states in 40-80 Angstrom diameter chemically synthesized CdSe quantum dots (QDs) at temperatures T = 1.2-50 K. The spin polarization is found not to saturate in magnetic fields to 60 T and time-resolved studies indicate a thermal population of exciton states. A simple model incorporating the angle-dependent Zeeman splitting and bright-dark level mixing in these randomly oriented quantum dots is constructed in quantitative agreement with the data. Fits using this model yield a dark exciton a factor of similar to0.9 at T = 1.45 K, which is independent of QD diameter and exhibits a surprising increase with increasing temperature.

引用

页数：5

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