Singlet-triplet transition tuned by asymmetric gate voltages in a quantum ring

被引：35

作者：

Fuhrer, A ^{[1
]}

Ihn, T

Ensslin, K

Wegscheider, W

Bichler, M

机构：

[1] ETH, Solid State Phys Lab, CH-8093 Zurich, Switzerland

[2] Univ Regensburg, Inst Expt & Angew Phys, D-93040 Regensburg, Germany

[3] Tech Univ Munich, Walter Schottky Inst, D-85748 Garching, Germany

来源：

PHYSICAL REVIEW LETTERS | 2003年 / 91卷 / 20期

关键词：

D O I：

10.1103/PhysRevLett.91.206802

中图分类号：

O4 [物理学];

学科分类号：

0702 ;

摘要：

Wave-function and interaction effects in the addition spectrum of a Coulomb-blockaded many-electron quantum ring are investigated as a function of asymmetrically applied gate voltages and magnetic field. Hartree and exchange contributions to the interaction are quantitatively evaluated at a crossing between states extended around the ring and states which are more localized in one arm of the ring. A gate tunable singlet-triplet transition of the two uppermost levels of this many-electron ring is identified at zero magnetic field.

引用

页数：4

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