标题： 飞秒电子结构工程在1$T$-TaS$_2$中的作用：掺杂和振幅模动力学的角色 显示英文标题

标题： Ultrafast Electronic Structure Engineering in 1$T$-TaS$_2$: Role of Doping and Amplitude Mode Dynamics

摘要： 在强关联过渡金属双硫属化合物中，多极子畸变、堆叠排列以及电子关联之间的复杂相互作用决定了绝缘态的性质。 在这里，我们研究了电子结构对光激发的响应，以揭示化学电子掺杂对该复杂相互作用的影响。 通过飞秒时间分辨光电子能谱测量了原始和电子掺杂的1$T$-TaS$_2$的瞬态变化，并将其与基于非平衡动力学平均场理论和密度泛函理论的理论建模进行比较。 电荷密度波振幅模式的振荡信号的细微变化表明库仑相互作用和跳跃存在相位依赖性修改。 此外，我们发现掺杂系统中单层的比例增加。 我们的工作展示了时间分辨光谱与先进的理论建模相结合如何为强关联过渡金属双硫属化合物的物理提供见解。 显示英文摘要

摘要： In strongly correlated transition metal dichalcogenides, an intricate interplay of polaronic distortions, stacking arrangement, and electronic correlations determines the nature of the insulating state. Here, we study the response of the electronic structure to optical excitations to reveal the effect of chemical electron doping on this complex interplay. Transient changes in pristine and electron-doped 1$T$ -TaS$_2$ are measured by femtosecond time-resolved photoelectron spectroscopy and compared to theoretical modeling based on non-equilibrium dynamical mean-field theory and density functional theory. The fine changes in the oscillatory signal of the charge density wave amplitude mode indicate phase-dependent modifications in the Coulomb interaction and the hopping. Furthermore, we find an enhanced fraction of monolayers in the doped system. Our work demonstrates how the combination of time-resolved spectroscopy and advanced theoretical modeling provides insights into the physics of correlated transition metal dichalcogenides.