Energy-level pinning and the 0.7 spin state in one dimension: GaAs quantum wires studied using finite-bias spectroscopy

被引：28

作者：

Graham, A. C. ^{[1
]}

Sawkey, D. L. ^{[1
]}

Pepper, M. ^{[1
]}

Simmons, M. Y. ^{[1
]}

Ritchie, D. A. ^{[1
]}

机构：

[1] Univ Cambridge, Cavendish Lab, Cambridge CB3 0HE, England

来源：

PHYSICAL REVIEW B | 2007年 / 75卷 / 03期

基金：

英国工程与自然科学研究理事会;

关键词：

D O I：

10.1103/PhysRevB.75.035331

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We study the effects of electron-electron interactions on the energy levels of GaAs quantum wires (QWs) using finite-bias spectroscopy. We probe the energy spectrum at zero magnetic field, and at crossings of opposite-spin-levels in high in-plane magnetic field B. Our results constitute direct evidence that spin-up (higher energy) levels pin to the chemical potential mu as they populate. We also show that spin-up and spin-down levels abruptly rearrange at the crossing in a manner resembling the magnetic phase transitions predicted to occur at crossings of Landau levels. This rearranging and pinning of subbands provides a phenomenological explanation for the 0.7 structure, a one-dimensional (1D) nanomagnetic state, and its high-B variants.

引用

页数：6

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