论文标题
（Tase4）2i中伪gap的双极性质，通过弱的光激发揭示
Bipolaronic nature of the pseudogap in (TaSe4)2I revealed via weak photoexcitation
论文作者
论文摘要
在许多密切相关的材料中，伪群的起源一直是一个长期的难题。在这里，我们发现了哪些多体相互作用是准二维（准1D）材料（Tase4）2i的伪合作，这是通过对材料的弱光启用来部分融化基态秩序的，从而揭示了差距中的基本状态。我们使用时间和角度分辨光发射光谱法观察到色散和平坦带的外观。我们将分散带分配给单粒子裸条带，而平面频带则将其分配给单极带的集合。我们的结果提供了直接的实验证据，表明小型荷斯坦极化子之间的多体相互作用，即双托龙的形成，主要负责（tase4）2i中的伪群。荷斯坦模型的最新理论研究支持了这种双极对两极的跨界的存在。我们还观察到（Tase4）2i（〜600 fs）激发的间隙状态的松弛时间截然不同，与另一种准1D材料RB0.3MOO3（〜60 fs）相比，它提供了一种新方法，该方法可区分由Polaronic或Luttinger或Luttinger-luttinger-Liquid-Liquid Many-Body Mover-Body Mover-Body Many-Body Mover-Body Many-Body互动。
The origin of the pseudogap in many strongly correlated materials has been a longstanding puzzle. Here, we uncover which many-body interactions underlie the pseudogap in quasi-one-dimensional (quasi-1D) material (TaSe4)2I by weak photo-excitation of the material to partially melt the ground state order and thereby reveal the underlying states in the gap. We observe the appearance of both dispersive and flat bands by using time- and angle-resolved photoemission spectroscopy. We assign the dispersive band to a single-particle bare band, while the flat band to a collection of single-polaron sub-bands. Our results provide direct experimental evidence that many-body interactions among small Holstein polarons i.e., the formation of bipolarons, are primarily responsible for the pseudogap in (TaSe4)2I. Recent theoretical studies of the Holstein model support the presence of such a bipolaron-to-polaron crossover. We also observe dramatically different relaxation times for the excited in-gap states in (TaSe4)2I (~600 fs) compared with another quasi-1D material Rb0.3MoO3 (~60 fs), which provides a new method for distinguishing between pseudogaps induced by polaronic or Luttinger-liquid many-body interactions.
