室温附近的铁磁力和可调节的异常霍尔效应在原子薄的Fe4CoGeTe2中
Shaohua Yan1,2, Hui-Hui He1,2, Yang Fu1,2
1Department of Physics and Beijing Key Laboratory of Optoelectronic Functional Materials & MicroNano Devices, Renmin University of China, Beijing 100872, China. hlei@ruc.edu.cn.
Nanoscale
|January 2, 2024
概括
接近室温的巡回铁磁性是通过添加铁 Telluride (Fe5GeTe2) 薄片实现的. 这一发现为先进的自旋电子设备提供了潜力,因为它具有强大的磁性和可调节的异常霍尔效应.
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
- 纳米技术纳米技术
背景情况:
- 巡回铁磁对旋转电子学至关重要,使旋转运输和操纵成为可能.
- 在超薄材料中实现室温铁磁性仍然是一个重大挑战.
研究的目的:
- 为了实现和调查室温附近的旅行铁磁在添加Fe5GeTe2薄片中.
- 探索这些材料的厚度依赖的磁性和传输特性.
- 了解铁磁的潜在机制和二维范德瓦尔斯磁铁中的异常霍尔效应.
主要方法:
- 用添加的Fe5GeTe2薄片的制造.
- 磁性特性的实验性表征,包括铁磁过渡温度 (TC).
- 在单层结构中预测铁磁性的理论计算.
- 测量异常的霍尔效应作为温度和厚度的函数.
主要成果:
- 在Co-doped Fe5GeTe2中观察到室温附近的巡回铁磁,TC约为323-337 K,厚度低至12 nm.
- 铁磁性持续到2nm (bilayer),TC约为284K,并预测存在于单层Fe4CoGeTe2.
- 观察到一种不寻常的温度和厚度依赖的内在异常霍尔效应.
- 异常的霍尔效应归因于厚度依赖的带结构修改,影响了Fermi水平附近的Berry曲率.
结论:
- 原子薄的Fe5GeTe2表现出强大的室温附近铁磁力和可调节的异常霍尔效应.
- 这些发现为2D范德瓦尔斯磁性材料的异国运输特性提供了洞察力.
- 这种材料对未来在自旋电子和低维磁器件中的应用具有前景.
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