在I-Mn-V半导体中,缺陷驱动的极端电磁阻
Junjie Yang1, Aaron Wegner1, Craig M Brown2
1Department of Physics, University of Virginia, Charlottesville, Virginia 22904, USA.
概括
这项研究揭示了抗铁磁半导体NaMnBi,由于Bi空缺,它表现出极端的磁阻力 (MR). 在室温以上观察到的这种独特特性,表明在微电子设备中的潜在应用.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 材料科学 材料科学
- 固态化学 固态化学
背景情况:
- 技术应用需要耐兴奋剂和热变化的材料.
- 反铁磁半导体具有独特的电子和磁性特性.
- 极端电磁阻 (MR) 是一个具有重大科学和技术意义的现象.
研究的目的:
- 调查四角形NaMnBi.Bi.中极端电磁阻的原因.
- 了解Bi空缺和轨道杂交在观测到的MR中的作用.
- 探索NaMnBi在微电子应用中的潜力.
主要方法:
- 合成和特征四角形NaMnBi与不同的Bi空置度.
- 在不同温度和磁场下测量磁阻.
- 分析磁矩重定向和电子传输特性.
主要成果:
- 当Bi空位存在时,四角形NaMnBi表现出极端的MR (>10000%在2K,600%在室温/9T).
- 双空缺引入电荷载体,将电子运输从半导体转向金属.
- 随着MR的增加,磁矩从对直线转向向倾斜的旋转安排发生了重新定位.
结论:
- 通过改变电子结构和传输,在NaMnBi中诱导极端MR至关重要.
- 在Mn和Bi轨道之间的杂交似乎对于场诱导的大型MR是必不可少的.
- NaMnBi是其类中独特的材料,具有极端的MR,具有微电子设备的潜力.
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