Intershell Exchange and Sequential Electrically Injected Spin Populations of InAs Quantum-Dot Shell States

被引：22

作者：

Kioseoglou, G. ^{[1
,4
]}

Yasar, M. ^{[2
]}

Li, C. H. ^{[1
]}

Korkusinski, M. ^{[3
]}

Diaz-Avila, M. ^{[2
]}

Hanbicki, A. T. ^{[1
]}

Hawrylak, P. ^{[3
]}

Petrou, A. ^{[2
]}

Jonker, B. T. ^{[1
]}

机构：

[1] USN, Res Lab, Washington, DC 20375 USA

[2] SUNY Buffalo, Dept Phys, Buffalo, NY 14260 USA

[3] CNR, Inst Microstruct Sci, Quantum Theory Grp, Ottawa, ON K1A 0R6, Canada

[4] Univ Crete, Dept Mat Sci & Technol, Iraklion 71003, Greece

来源：

PHYSICAL REVIEW LETTERS | 2008年 / 101卷 / 22期

基金：

美国国家科学基金会;

关键词：

D O I：

10.1103/PhysRevLett.101.227203

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We report sequential spin population of individual shell states of self-assembled InAs quantum dots controlled by a spin-polarized current from an Fe contact, and determine the s-p and p-d intershell exchange energies. We resolve excitonic features in the electroluminescence (EL) spectra associated with individual quantum levels. In contrast with simple models of shell occupation, the EL circular polarization exhibits maxima shifted with respect to the intensity peaks. Calculations show that this is due to intershell exchange. Exchange energies for the s-p and p-d shells are 7 +/- 2 and 13.5 +/- 1 meV, respectively.

引用

页数：4

共 27 条

[1] Hidden symmetries in the energy levels of excitonic 'artificial atoms' [J].