在磁拓绝缘体中通过共振红外磁性循环二元制探测果曲率
Seul-Ki Bac1,2,3, Florian Le Mardelé4, Jiashu Wang1
1University of Notre Dame, Department of Physics and Astronomy, Notre Dame, Indiana 46556, USA.
Physical review letters
|February 6, 2025
概括
研究人员在MnBi2Te4中观察到磁圆二重化 (MCD),与异常的霍尔效应相关. 这种光学方法揭示了磁性材料的拓相变,提供了一种检测贝里曲率的新方法.
科学领域:
- 凝聚物质物理学 凝聚物质物理学
- 材料科学 是一种材料科学.
- 量子拓学是一种量子拓学.
背景情况:
- 在凝聚物质中研究量子几何和拓学通常使用磁场下的静态电子传输.
- 这些属性的非接触式光学测量尚未得到充分探索.
研究的目的:
- 探索无接触光学测量,用于探测量子几何和拓学.
- 在MnBi2Te4薄膜中观察和描述磁圆二重化 (MCD).
- 为了将MCD与电子传输现象和拓相位过渡相关联.
主要方法:
- 红外光谱测量共振磁圆二重化 (MCD). 红外光谱测量共振磁圆二重化.
- 应用磁场来诱导MnBi2Te4薄膜中的相位过渡.
- 将MCD与贝里曲率和异常霍尔效应相关的理论建模.
- 密度函数理论 (DFT) 的计算.
主要成果:
- 在MnBi2Te4薄膜中观察到红外波段的共振MCD.
- MCD的光谱强度与异常的霍尔效应在场驱动的反铁磁到倾斜的铁磁相位过渡期间相关.
- 理论分析证实,MCD发作意味着从拓绝缘体到化切尔恩绝缘体的拓相过渡.
- DFT计算表明MCD起源于Brillouin区域边缘光学转换,这是一个新的Berry曲率源.
结论:
- 响应MCD是一种可行的无接触光学探头,用于磁性材料中的量子几何和拓.
- 这项研究展示了一种用于检测贝里曲率的新型光谱方法.
- 这些发现突出了超越 Γ 点的磁性材料中的潜在的新曲源.
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