在分层的极性半导体中观察异常的霍尔效应
Seo-Jin Kim1, Jihang Zhu2, Mario M Piva1
1Max Planck Institute for Chemical Physics of Solids, 01187, Dresden, Germany.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|December 8, 2023
概括
研究人员在极性半导体AgCrSe2.2中发现了一种自发的异常霍尔效应 (AHE). 这一发现为磁电材料提供了一条新的途径,通过将时间逆向对称性破坏与极性结构相结合.
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:
- 磁电材料需要破碎的时间逆向对称性和极性铁电结构,这在传统磁铁中往往是矛盾的.
- 最近在非对线磁体和变磁体中发现异常的霍尔效应 (AHE) 提供了替代途径,但这些材料通常缺乏极性.
研究的目的:
- 报告在多层极性半导体中观察到自发的AHE,该半导体被添加AgCrSe2.
- 调查观察到的AHE的特征和潜在机制.
- 探索这种材料在磁电设备中的应用潜力.
主要方法:
- 杂AgCrSe2.2.的实验合成和表征
- 在不同磁场角度下测量异常的霍尔电阻.
- 离子门实验调节载体密度并研究其对AHE的影响.
- 理论计算以了解贝里曲率和磁性相关性的作用.
主要成果:
- 在具有反铁磁合的分层极性半导体AgCrSe2中观察自发的AHE.
- 异常的霍尔电阻力与在补偿磁系统中观察到的最大电阻力相当.
- 在旋转磁场 (距离c轴约80°) 时快速关闭AHE.
- 通过调节p型载体密度来增强异常的霍尔导电性通过离子门.
结论:
- 观察到的AHE是由贝里曲率驱动的,这是由于Cr.旋转之间的非线性反铁磁相关性.
- 杂的AgCrSe2为探索磁性和铁电类反应的相互作用提供了一个有前途的平台.
- 这一发现为开发新型磁电材料开辟了新的途径.
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