Low-energy electronic spin excitations between filling factors ν=1 and 1/2 studies by optically detected nuclear magnetic resonance

被引：6

作者：

Brockbank, RL ^{[1
]}

Davies, HDM ^{[1
]}

Ryan, JF ^{[1
]}

Thomson, MA ^{[1
]}

Turberfield, AJ ^{[1
]}

机构：

[1] Univ Oxford, Dept Phys, Clarendon Lab, Oxford OX1 3PU, England

来源：

PHYSICA E | 2000年 / 6卷 / 1-4期

关键词：

NMR; fractional quantum Hall effect; Skyrmion;

D O I：

10.1016/S1386-9477(99)00091-0

中图分类号：

TB3 [工程材料学];

学科分类号：

0805 ; 080502 ;

摘要：

We report measurements of the spin relaxation time (T-1n) for nuclei in the potential well confining a high-mobility two-dimensional electron system at a single GaAs-GaAlAs heterojunction. At low temperature nuclear spin relaxation is dominated by electron-nuclear spin scattering: we find that T-1n displays sharp maxima at incompressible states throughout the v = 2/3 hierarchy of the fractional quantum Hall effect. This behaviour is consistent with the existence of low-energy spin excitations only where the electron system is compressible. Our measurements also provide evidence for a gap in the spin excitation spectrum at v = 1/2. (C) 2000 Published by Elsevier Science B.V. All rights reserved.

引用

页码：56 / 59

页数：4

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