期刊
JOURNAL OF THE EUROPEAN CERAMIC SOCIETY
卷 26, 期 14, 页码 3017-3025出版社
ELSEVIER SCI LTD
DOI: 10.1016/j.jeurceramsoc.2006.02.021
关键词
powders-solid state reaction; X-ray methods; magnetic properties; ZnO; room temperature ferromagnetic semiconductors
The reactivity of the Zn-Mn-O system, prepared by conventional ceramic routes using ZnO and MnO2 as starting materials are described and correlated with the magnetic response. X-ray diffraction, X-ray photoelectron spectroscopy and Raman spectroscopy techniques have been used for the structural analysis. The ferromagnetic response is unambiguously determined to be due to the simultaneous presence of Mn+3 and Mn+4 ions at the Zn diffusion front into the manganese oxide grain. Thus, it is demonstrated that Mn does not incorporate into the ZnO lattice substitutionally, but it is the Zn that diffuses into the manganese oxide grains, acting as a retardant of the manganese reduction, Mn+4 -> Mn+3. At the diffusion front, both ions coexist and their spins couple ferromagnetically through a double exchange mechanism. This mechanism explains the origin of the room temperature ferromagnetism recently discovered in Zn-Mn-O system as a promising material for spintronic devices. (c) 2006 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据