Impact of amorphization on the magnetic properties of EuO-TiO2 system

被引：12

作者：

Akamatsu, Hirofumi ^{[1
]}

Fujita, Koji ^{[1
]}

Zong, Yanhua ^{[1
]}

Takemoto, Naohiro ^{[1
]}

Murai, Shunsuke ^{[1
]}

Tanaka, Katsuhisa ^{[1
]}

机构：

[1] Kyoto Univ, Dept Chem Mat, Grad Sch Engn, Nishikyo Ku, Kyoto 6158510, Japan

来源：

PHYSICAL REVIEW B | 2010年 / 82卷 / 22期

关键词：

CRYSTAL-CHEMISTRY; OPTICAL BASICITY; BORATE GLASSES; SPIN-GLASSES; THIN-FILMS; EUROPIUM; MOSSBAUER; DYNAMICS; EUTIO3; FERROMAGNET;

D O I：

10.1103/PhysRevB.82.224403

中图分类号：

T [工业技术];

学科分类号：

120111 [工业工程];

摘要：

Recently, we have reported amorphization-induced ferromagnetism in a magnetic oxide; whereas crystalline EuTiO3 is an antiferromagnet, its amorphous counterpart shows a ferromagnetic transition. In this paper, we have investigated the magnetic properties of amorphous EuO-TiO2 system in detail. The present compounds, i.e., amorphous EuTiO3 and Eu2TiO4, exhibit a paramagnetic-ferromagnetic transition followed by a spin-glass transition upon cooling down, thereby being characterized as reentrant ferromagnets. Interestingly, the magnetic ordering temperatures of amorphous EuTiO3 and Eu2TiO4 are comparable to and higher than those of their crystalline counterparts, respectively, indicating the enhancement of ferromagnetic interactions by amorphization. The origin of these features is discussed in terms of both the essential structural difference between amorphous and crystalline oxides and the magnetism unique to the crystalline EuO-TiO2 compounds. We also find a correlation between the magnitude of ferromagnetic interactions and the covalency of Eu-O bonds.

引用

页数：8

共 40 条

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