Giant magnetoresistance and quantum phase transitions in strongly localized magnetic two-dimensional electron gases

被引：38

作者：

Smorchkova, IP

Samarth, N ^{[1
]}

Kikkawa, JM

Awschalom, DD

机构：

[1] Penn State Univ, Dept Phys, University Pk, PA 16802 USA

[2] Univ Calif Santa Barbara, Dept Phys, Santa Barbara, CA 93106 USA

来源：

PHYSICAL REVIEW B | 1998年 / 58卷 / 08期

关键词：

D O I：

10.1103/PhysRevB.58.R4238

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The application of a small magnetic field (B approximate to 0.1T) either parallel or perpendicular to a low-density (approximate to 10(11) cm(-2)) magnetic two-dimensional electron gas (2DEG) creates a striking positive magnetoresistance of up to 700%. This is a spin effect, caused by the suppression of spin-dependent hopping paths between localized states with on-site correlation. At higher fields, a spin-related delocalization is observed. In the perpendicular field geometry, orbital effects combine with this delocalization and lead to quantum phase transitions between the spin-polarized insulating state and the nu=1 quantum Hall liquid.

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收藏

页码：R4238 / R4241

页数：4

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