论文标题
照片诱导的电荷动力学在1 $ t $ -tas $ _2 $中
Photo-induced charge dynamics in 1$T$-TaS$_2$
论文作者
论文摘要
最近的理论研究表明,低温电荷密度波相中的1 $ t $ -tas $ _2 $的电子结构表现出带构成和莫特绝缘行为之间的非平凡相互作用。这对兴奋剂实验的解释具有重要意义。在这里,我们使用逼真的多层结构的非平衡动力学平均场理论模拟来阐明激光脉冲引起的电荷载体动力学。通过采用内存截断方案,将解决方案传播到Picsecond TimeScale。虽然长寿命的双龙和圆顶仅存在于特定结构的表面状态,但构成系统大部分系统的双层粘结状态的干扰解释了差距内几乎瞬时的外观。我们的模拟始终在以前的时间分辨光发射实验中与突出的``背景''信号一起解释了Doublon特征的共存,它们通过利用对泵极化和泵频率的敏感性来为Ingap和Doublon状态的选择性人群提供策略。
Recent theoretical studies showed that the electronic structure of 1$T$-TaS$_2$ in the low-temperature commensurate charge density wave phase exhibits a nontrivial interplay between band-insulating and Mott insulating behavior. This has important implications for the interpretation of photo-doping experiments. Here we use nonequilibrium dynamical mean-field theory simulations of a realistic multi-layer structure to clarify the charge carrier dynamics induced by a laser pulse. The solution is propagated up to the picosecond timescale by employing a memory-truncation scheme. While long-lived doublons and holons only exist in the surface state of a specific structure, the disturbance of bonding states in the bilayers which make up the bulk of the system explain the almost instantaneous appearance of in-gap states. Our simulations consistently explain the coexistence of a doublon feature with a prominent ``background" signal in previous time-resolved photoemission experiments, and they suggest strategies for the selective population of the ingap and doublon states by exploiting the sensitivity to the pump polarization and pump frequency.