Absence of ferromagnetic order in high quality bulk Co-doped ZnO samples

被引：46

作者：

de Carvalho, H. B. ^{[1
]}

de Godoy, M. P. F. ^{[2
]}

Paes, R. W. D. ^{[3
]}

Mir, M. ^{[1
]}

Ortiz de Zevallos, A. ^{[4
]}

Iikawa, F. ^{[4
]}

Brasil, M. J. S. P. ^{[4
]}

Chitta, V. A. ^{[5
]}

Ferraz, W. B. ^{[6
]}

Boselli, M. A. ^{[3
,6
]}

Sabioni, A. C. S. ^{[4
]}

机构：

[1] Univ Fed Alfenas, BR-37130000 Alfenas, MG, Brazil

[2] Univ Fed ABC, BR-09210170 Sao Paulo, Brazil

[3] Univ Fed Ouro Preto, BR-35400000 Ouro Preto, MG, Brazil

[4] Univ Estadual Campinas, Inst Fis Gleb Wataghin, BR-13083970 Campinas, SP, Brazil

[5] Univ Sao Paulo, Inst Fis, BR-05315970 Sao Paulo, Brazil

[6] Ctr Desenvolvimento Tecnol Nucl CNEN, BR-31270901 Belo Horizonte, MG, Brazil

来源：

JOURNAL OF APPLIED PHYSICS | 2010年 / 108卷 / 03期

基金：

巴西圣保罗研究基金会;

关键词：

ELECTRICAL SPIN INJECTION; MAGNETIC-PROPERTIES; THIN-FILMS; METAL; TEMPERATURE;

D O I：

10.1063/1.3459885

中图分类号：

O59 [应用物理学];

学科分类号：

摘要：

Bulk Zn1-xCoxO samples were synthesized via standard solid-state reaction route with different Co molar concentrations up to 21%. A detailed microstructural analysis was carried out to investigate alternative sources of ferromagnetism, such as secondary phases and nanocrystals embedded in the bulk material. Conjugating different techniques we confirmed the Zn replacement by Co ions in the wurtzite ZnO structure, which retains, however, a high crystalline quality. No segregated secondary phases neither Co-rich nanocrystals were detected. Superconducting quantum interference device magnetometry demonstrates a paramagnetic Curie-Weiss behavior with antiferromagnetic interactions. We discuss the observed room temperature paramagnetism of our samples considering the current models for the magnetic properties of diluted magnetic semiconductors. (C) 2010 American Institute of Physics. [doi: 10.1063/1.3459885]

引用

页数：5

共 34 条

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