在YTiO3中引起的高温铁磁性
A S Disa1,2, J Curtis3,4, M Fechner5
1Max Planck Institute for the Structure and Dynamics of Matter, Hamburg, Germany. asd47@cornell.edu.
Nature
|May 3, 2023
概括
研究人员使用光来增强YTiO3的铁磁性,达到高达80K的短暂磁性,远远超过其通常的27K极限. 这种光学控制为设计量子材料特性提供了新的途径.
科学领域:
- 量子材料科学
- 凝聚物质物理学
- 材料工程
背景情况:
- 量子材料中的退化和挫折相互作用通常会抑制所需的电子或磁相.
- 设计这些阶段的传统方法涉及原子结构的修改,受到热力学约束的限制.
- 酸 (YTiO3) 具有低基里温度 (Tc = 27K) 的抑制铁磁性.
研究的目的:
- 为了研究晶格动态的全光学选择性操纵.
- 增强和稳定YTiO3的高温铁磁性超出其平衡限制.
- 探索量子材料中的光诱导的非平衡功能.
主要方法:
- 采用了9 THz的YTiO3晶格的选择性光学激发.
- 研究激发特定氧气旋转模式对磁性特性的影响.
- 分析了 (Ti) t2g轨道的光诱导的动态变化及其对磁相竞争的影响.
主要成果:
- 在低温下在YTiO3中达到完全的磁和.
- 到超过80K的非平衡温度 (Tneq) 实现过渡性铁磁,几乎是热力学Tc的三倍.
- 在纳米秒时间尺度上观察到光诱导的铁磁.
结论:
- 所有光学晶格操纵可以动态增强和稳定量子材料中的铁磁性.
- 准退化轨道的光诱导变化是克服平衡限制的关键.
- 这种方法使得非平衡功能的动态工程可用于实际应用.
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