论文标题
通过互补的超快光谱技术对非平衡状态进行强度相关的材料的研究
Investigation of the Non-equilibrium State of Strongly Correlated Materials by Complementary Ultrafast Spectroscopy Techniques
论文作者
论文摘要
光诱导的非热相变是强烈相关材料的外来非平衡物理学的新范式。超短光脉冲可以通过在平衡状态下不会发生的复杂微观相互作用将系统驱动到新阶。超快光谱镜是揭示此类过渡的基本机制的独特工具，从而导致物质的短暂阶段。然而，他们的个人特异性通常并不提供物理问题的详尽图景。提高其性能的一种有效解决方案是整合不同的超快技术。这提供了一个机会，可以从不同的角度同时探测物理现象，同时保持相同的实验条件。在这种情况下，我们通过结合时间分辨的反射率以及时间和角度分辨光发射光谱来进行互补实验。我们通过研究1 $ \ it {t} $ - tise $ _ {2} $的复杂电荷密度波（CDW）阶段来证明这种组合方法的优势。具体而言，我们展示了晶格自由度在此材料中建立和稳定CDW的关键作用。
Photoinduced non-thermal phase transitions are new paradigms of exotic non-equilibrium physics of strongly correlated materials. An ultrashort optical pulse can drive the system to a new order through complex microscopic interactions that do not occur in the equilibrium state. Ultrafast spectroscopies are unique tools to reveal the underlying mechanisms of such transitions which lead to transient phases of matter. Yet, their individual specificities often do not provide an exhaustive picture of the physical problem. One effective solution to enhance their performance is the integration of different ultrafast techniques. This provides an opportunity to simultaneously probe physical phenomena from different perspectives whilst maintaining the same experimental conditions. In this context, we performed complementary experiments by combining time-resolved reflectivity and time and angle-resolved photoemission spectroscopy. We demonstrated the advantage of this combined approach by investigating the complex charge density wave (CDW) phase in 1$\it{T}$-TiSe$_{2}$. Specifically, we show the key role of lattice degrees of freedom to establish and stabilize the CDW in this material.
