论文标题
在室温下成像激子绝缘子候选者ta $ _2 $ _5 $中集体模式的连贯繁殖
Imaging the coherent propagation of collective modes in the excitonic insulator candidate Ta$_2$NiSe$_5$ at room temperature
论文作者
论文摘要
激子绝缘子以平衡构成电子孔对的冷凝物，从而产生集体多体效应。尽管有几种材料作为激子绝缘子候选物出现，但缺乏远距离连贯性的证据，并且在这些系统中，有序阶段的起源仍然存在争议。在这里，使用Ultrafast Pump-probe显微镜，我们研究了可能的激光绝缘子TA $ _2 $ nise $ _5 $。在328 K以下，我们观察到以$ \ sim10^5 $ m/s的速度下的相干模式的异常尺度传播，我们将其归因于声子模式与冷凝水的相位模式之间的杂交。我们开发了一个理论框架来支持这一解释，并提出电子交互作用为ta $ _2 $ nise $ _5 $中的有序阶段提供了重要贡献。这些结果使我们能够了解冷凝物的集体模式如何运输能源并与其他自由度相互作用。我们的研究为在强相关材料中研究和操纵这些特性提供了独特的范式。
Excitonic insulators host a condensate of electron-hole pairs at equilibrium, giving rise to collective many-body effects. Although several materials have emerged as excitonic insulator candidates, evidence of long-range coherence is lacking and the origin of the ordered phase in these systems remains controversial. Here, using ultrafast pump-probe microscopy, we investigate the possible excitonic insulator Ta$_2$NiSe$_5$. Below 328 K, we observe the anomalous micrometer-scale propagation of coherent modes at velocities of the order of $\sim10^5$ m/s, which we attribute to the hybridization between phonon modes and the phase mode of the condensate. We develop a theoretical framework to support this explanation and propose that electronic interactions provide a significant contribution to the ordered phase in Ta$_2$NiSe$_5$. These results allow us to understand how the condensate's collective modes transport energy and interact with other degrees of freedom. Our study provides a unique paradigm for the investigation and manipulation of these properties in strongly correlated materials.
