Competing mechanisms for singlet-triplet transition in artificial molecules

被引：36

作者：

Bellucci, D

Rontani, M

Troiani, F

Goldoni, G

Molinari, E

机构：

[1] Univ Modena & Reggio Emilia, INFM, Natl Res Ctr Nanostruct & Biosyst Surfaces, I-41100 Modena, Italy

[2] Univ Modena & Reggio Emilia, Dipartimento Fis, I-41100 Modena, Italy

来源：

PHYSICAL REVIEW B | 2004年 / 69卷 / 20期

关键词：

D O I：

10.1103/PhysRevB.69.201308

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We study the magnetic field induced singlet/triplet transition for two electrons in vertically-coupled quantum dots by exact diagonalization of the Coulomb interaction. We identify the different mechanisms occurring in the transition, involving either in-plane correlations or localization in opposite dots, depending on the field direction. Therefore, both spin and orbital degrees of freedom can be manipulated by field strength and direction. The phase diagram of realistic devices is determined.

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页码：201308 / 1

页数：4

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