Origin of large positive magnetoresistance in the hard-gap regime of epitaxial Co-doped ZnO ferromagnetic semiconductors

被引：32

作者：

Tian, Y. F. ^{[1
,2
]}

Yan, Shi-shen ^{[1
]}

Cao, Q. ^{[1
]}

Deng, J. X. ^{[1
]}

Chen, Y. X. ^{[1
]}

Liu, G. L. ^{[1
]}

Mei, L. M. ^{[1
]}

Qiang, Y. ^{[2
]}

机构：

[1] Shandong Univ, Sch Phys, Jinan 250100, Shandong, Peoples R China

[2] Univ Idaho, Dept Phys, Moscow, ID 83844 USA

来源：

PHYSICAL REVIEW B | 2009年 / 79卷 / 11期

关键词：

cobalt; electrical resistivity; ferromagnetic materials; hopping conduction; II-VI semiconductors; magnetic semiconductors; magnetic thin films; magnetoresistance; molecular beam epitaxial growth; semiconductor epitaxial layers; spin polarised transport; wide band gap semiconductors; zinc compounds; HOPPING REGIME; MAGNETIC SEMICONDUCTORS; EXCHANGE; CONDUCTIVITY; TRANSPORT; FILMS;

D O I：

10.1103/PhysRevB.79.115209

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

We studied the electrical transport properties of single-crystal epitaxial Co-doped ZnO films grown by molecular-beam epitaxy. Upon increasing temperature, transport mechanisms changed from hard-gap resistance to Efros variable range hopping. The magnetic field and the temperature dependence of magnetoresistance revealed that large positive magnetoresistance observed in the hard-gap regime originated from the shrinkage of electron wave functions. However, no sign of spin-dependent transport behavior was found.

引用

页数：5

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