Correlated Electrons in Optically Tunable Quantum Dots: Building an Electron Dimer Molecule

被引：37

作者：

Singha, Achintya ^{[1
,2
]}

Pellegrini, Vittorio ^{[1
,2
]}

Pinczuk, Aron ^{[3
,4
,5
]}

Pfeiffer, Loren N. ^{[6
,8
]}

West, Ken W. ^{[6
,8
]}

Rontani, Massimo ^{[7
]}

机构：

[1] CNR, NEST, Ist Nanosci, I-56127 Pisa, Italy

[2] Scuola Normale Super Pisa, I-56127 Pisa, Italy

[3] Columbia Univ, Dept Appl Phys, New York, NY 10027 USA

[4] Columbia Univ, Dept Appl Math, New York, NY 10027 USA

[5] Columbia Univ, Dept Phys, New York, NY 10027 USA

[6] Princeton Univ, Dept Elect Engn, Princeton, NJ 08544 USA

[7] CNR, Ist Nanosci, S3, I-41125 Modena, Italy

[8] Alcatel Lucent, Bell Labs, Murray Hill, NJ 07974 USA

来源：

PHYSICAL REVIEW LETTERS | 2010年 / 104卷 / 24期

基金：

美国国家科学基金会;

关键词：

MAGNETIC-FIELD; SPECTROSCOPY; EXCITATIONS; SCATTERING; MOTION;

D O I：

10.1103/PhysRevLett.104.246802

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

We observe the low-lying excitations of a molecular dimer formed by two electrons in a GaAs semiconductor quantum dot in which the number of confined electrons is tuned by optical illumination. By employing inelastic light scattering we identify the intershell excitations in the one-electron regime and the distinct spin and charge modes in the interacting few-body configuration. In the case of two electrons, a comparison with configuration-interaction calculations allows us to link the observed excitations with the breathing mode of the molecular dimer and to determine the singlet-triplet energy splitting.

引用

页数：4

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