Spin-orbit dilution effects on the magnetism of frustrated spinel Ge(Co1-xMgx)2O4

International Conference on Strongly Correlated Electron Systems 2014

Agata, Ryotaro^1 ; Takita, Shota^1 ; Ishikawa, Takashi^1 ; Watanabe, Tadataka^1

Department of Physics, College of Science and Technology (CST), Nihon University, Chiyoda-ku, Tokyo

101-8308, Japan^1

关键词: Antiferromagnetic orderings;    Dilution effect;    Ferro-magnetic interactions;    Nonmagnetics;    Spin orbits;    Spin-glass behavior;    Spinel oxide;    Weiss temperatures;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/592/1/012106/pdf
DOI  :  10.1088/1742-6596/592/1/012106

来源: IOP

【 摘 要 】

We investigated magnetic properties of spinel oxides Ge(Co1-xMgx)2O4with x= 0 ∼ 0.5 to study the spin-orbit dilution effects on the magnetism of spin-orbit frustrated spinel GeCo2O4. We discovered that the magnetic moment per single Co2+ion is decreased with increasing nonmagnetic Mg2+concentration, which indicates the spin-orbit decoupling caused by the spin-orbit dilution. Additionally, small-amount substitution of Mg2+for Co2+causes the rapid increase of the positive Weiss temperature indicating the enhancement of ferromagnetic interactions, while the Mg2+substitution suppresses the antiferromagnetic ordering resulting in the appearance of spin glass behavior. The present results suggest that the spin-orbit dilution causes the spin-orbit decoupling and the reinforcement of ferromagnetic frustration in GeCo2O4.