在有机离子间隔的CrSBrBr中200K以上的铁磁性
Sofia Ferreira-Teixeira1, Daniel Tezze1,2, Maria Ramos1,3
1CIC nanoGUNE BRTA, Donostia-San Sebastian 20018, Spain.
ACS nano
|October 9, 2025
概括
将分子插入硫化 (CrSBr) 中,将其反铁磁状态转化为强大的铁磁状态. 这种方法提高了磁性过渡温度,为先进的二维磁器件铺平了道路.
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:
- 硫化化 (CrSBr) 是一种2D范德瓦尔斯半导体,其抗铁磁性能低于140K.
- 它的磁性,电子性和光学性质可以通过外部刺激来调整,使其成为2D磁性的平台.
- 作为调整 CrSBr 磁性的策略,分子间隔仍然在很大程度上未被探索.
研究的目的:
- 调查分子间隙对 CrSBr.Br 的磁性特性的影响.
- 探索互的潜力,以提高磁过渡温度,并诱导新的磁顺序.
- 为了评估间隔的CrSBr.Br的空气稳定性和磁阻力.
主要方法:
- 甲基 (TMA) 和四甲基 (TPA) 离子间隔成CrSBr.Br.
- 测量磁性属性以确定磁性顺序和过渡温度.
- 拉曼显微镜和密度函数理论 (DFT) 计算来分析结构变化.
主要成果:
- 在CrSBr中,TMA和TPA离子的间隙诱导了从反铁磁到铁磁顺序的过渡.
- 磁性过渡温度显著提高到TMA的190K和TPA的230K.
- 由此产生的间酸盐在空气中稳定,并且显示出很大的歇斯底里性磁电阻 (TPA在50K的情况下高于60%).
- 间隔时观察到破坏对称性的结构变化,由拉曼显微镜和DFT证实.
结论:
- 分子间隔是调整 CrSBr.Br 的磁性特性的一种强有力的方法.
- 间隙使得能够制造出坚固,高温的2D磁性材料.
- 这种方法提供了一种多功能途径,可以在多层材料中设计新的磁性功能.
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