论文标题
FERH中抗铁磁 - 铁磁相变的超快动力学
Ultrafast kinetics of the antiferromagnetic-ferromagnetic phase transition in FeRh
论文作者
论文摘要
了解短期互动构建长期顺序的速度是凝结物理学中最有趣的主题之一。 FERH是用于研究磁性问题的测试标本，其中微观自旋旋转交换相互作用最终是铁磁性宏观或抗磁性宏观秩序的原因。飞秒激光激发可以诱导抗磁磁性FERH中的铁磁性，但是这种过渡的机制和动力学是激烈辩论的主题。采用双泵THZ发射光谱，使我们能够显着增加瞬时状态的THZ发射探针的时间检测窗口，而无需牺牲任何分辨率或灵敏度的损失。它使我们能够研究从飞秒到FERH/PT双层中的纳秒时间尺度的新兴铁磁学的动力学。我们的结果强烈表明，在初始泵激发与铁磁核对THZ辐射的发射之间存在潜伏期。
Understanding how fast short-range interactions build up long-range order is one of the most intriguing topics in condensed matter physics. FeRh is a test specimen for studying this problem in magnetism, where the microscopic spin-spin exchange interaction is ultimately responsible for either ferro- or antiferromagnetic macroscopic order. Femtosecond laser excitation can induce ferromagnetism in antiferromagnetic FeRh, but the mechanism and dynamics of this transition are topics of intense debates. Employing double-pump THz emission spectroscopy has enabled us to dramatically increase the temporal detection window of THz emission probes of transient states without sacrificing any loss of resolution or sensitivity. It allows us to study the kinetics of emergent ferromagnetism from the femtosecond up to the nanosecond timescales in FeRh/Pt bilayers. Our results strongly suggest a latency period between the initial pump-excitation and the emission of THz radiation by ferromagnetic nuclei.
