抗铁磁半导体 BaFMn0.5Te 具有独特的 Mn 排序和红色光发
Haijie Chen1,2, Rebecca McClain1, Jiangang He3
1Department of Chemistry , Northwestern University , Evanston , Illinois 60208 , United States.
Journal of the American Chemical Society
|October 8, 2019
概括
我们合成了一种新型的半导体BaFMn0.5Te, 由于其独特的磁性和光学特性,该材料对光旋电子应用具有前景.
科学领域:
- 材料科学
- 凝聚物质物理学
- 半导体物理
背景情况:
- 具有联合磁性和光电子性质的半导体对于光旋电子技术的发展至关重要.
- 开发具有定制功能的新材料对于下一代电子设备至关重要.
研究的目的:
- 合成和表征一种新的混合离子半导体,BaFMn0.5Te,具有潜在的光旋电子应用.
- 为了研究BaFMn0.5Te的磁性和光发光特性.
主要方法:
- 使用"全景合成"技术和同步辐射合成BaFMn0.5Te.
- 使用 (3+1) 维超空间组的结构改进.
- 使用光谱学和第一原理计算对磁性 (抗铁磁) 和光电子性 (光发光) 的表征.
主要成果:
- 成功合成了BaFMn0.5Te,带隙为1.76 eV,工作功率为5.08 eV.
- 观察到90K以下的反铁磁性 (AFM) 和以700nm为中心的强红色光发光 (PL).
- 确定了ZrCuSiAs类层结构,由于Mn2+排序而具有相应的调制结构.
- 第一原理计算证实了来自Te 5p和Mn 3d轨道和反铁磁相互作用的间接带间隙.
结论:
- BaFMn0.5Te是一种新的混合离子半导体,具有同时存在的抗铁磁性和强红色光发光特性.
- 该材料的独特结构和电子特性使其成为光旋电子应用的有希望的候选者.
- 时间解析的PL数据表明材料内的多种发射状态和能量传递机制.
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