Time-resolved, angle-resolved photoemission spectroscopy (TR-ARPES) is a one-particle spectroscopic technique that can probe excitons (two-particle excitations) in momentum space. We present an ab initio, time-domain GW approach to TR-ARPES and apply it to monolayer MoS$_2$. We show that photoexcited excitons may be measured and quantified as satellite bands, as well as leading to the renormalization of the quasiparticle bands. These features are explained in terms of an exciton- Floquet phenomenon induced by an exciton time-dependent bosonic field, which is orders of magnitude stronger than laser field induced Floquet bands in low-dimensional semiconductors. Our findings open a door to understanding the behavior of optical-field driven materials.
Symmetry-Driven Floquet Engineering in Multivalley SnS
Université de Bordeaux(波尔多大学);Max Planck Institute for the Structure and Dynamics of Matter(马普物质结构与动力学研究所);Università degli Studi di Palermo(巴勒莫大学);Universidad del País Vasco UPV/EHU(巴斯克地区大学);The Flatiron Institute(平顿研究所)
Tsinghua University(清华大学);State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University(清华大学低维量子物理国家重点实验室);Frontier Science Center for Quantum Information(量子信息前沿科学中心)
Tsinghua University(清华大学);State Key Laboratory of Low-Dimensional Quantum Physics, Tsinghua University(清华大学低维量子物理国家重点实验室);Frontier Science Center for Quantum Information(量子信息前沿科学中心)
Phonon-driven Floquet engineering for electronic states
National Institute for Materials Science(物质材料研究机构);National Yang Ming Chiao Tung University(国立阳明交通大学);National Synchrotron Radiation Research Center(国立同步辐射研究中心);Kyoto University(京都大学);Nihon University(日本大学)
Layer and orbital interference effects in photoemission from transition metal dichalcogenides
在这项工作中,我们提供了一个有效的模型来评估单电子偶极矩阵元管理的光激发和光电发射过程的单层(SL)和双层(BL)过渡金属二硫族化物。通过利用$\vec{k} \cdot \vec{p}$哈密顿量,我们计算的光电发射强度,从周围的$_2$的$\bar{K}$ -谷的价带角分辨光电发射中观察到的。在SL MoS $_2$中,我们发现在第一布里渊区之外的强度的显著掩蔽,这源于从Mo $d$轨道发射的光电子之间的面内干涉效应。在BL MoS $_2$中,额外的层间干涉效应导致强度与光子能量的独特调制。最后,我们使用半导体布洛赫方程来模拟时间和角度分辨泵浦探测光电发射实验中的光激发。我们发现,导带中的光激发的人口的动量依赖性导致在SL和BL MOS $_2$可观察到的二向色性。
Time-resolved ARPES in pumped excitonic systems: Floquet physics induced by excitonic fields
Dipartimento di Fisica “E.R. Caianiello”, Università degli Studi di Salerno(萨莱诺大学 E.R. 卡亚涅洛物理系);CNR-SPIN, Unità di Salerno(意大利国家研究委员会 SPIN 研究所萨莱诺分部);CNISM, Unità di Salerno, Università degli Studi di Salerno(萨莱诺大学 CNISM 研究所萨莱诺分部)
Floquet dressing of bulk metallic bands in 2H-NbSe2
Beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences(中国科学院物理研究所凝聚态物理国家实验室);Department of Applied Physics, KTH Royal Institute of Technology(瑞典皇家理工学院应用物理系)
Time-resolved observation of magnon splitting into vortex gyration and Floquet spin waves
Université Paris-Saclay, CNRS, Centre de Nanosciences et de Nanotechnologies(巴黎萨克雷大学);Helmholtz-Zentrum Dresden–Rossendorf(德累斯顿-罗森多夫亥姆霍兹中心);International Iberian Nanotechnology Laboratory(伊比利亚纳米技术国际实验室)
Polarization-Modulated Angle-Resolved Photoemission Spectroscopy: Towards Circular Dichroism without Circular Photons and Bloch Wavefunction Reconstruction
Floquet engineering of titled and gapped Dirac materials
我们已经建立了一个严格的理论形式主义Floquet工程,或调查,并最终定制最关键的电子性质的四硫化钼(1 T $^\prime$ -MoS $_2$),通过施加外部高频修整场在非共振制度。最近的研究表明,单层掺杂的1 T $^\prime$ -MoS $_2$可以呈现出扭曲的四元结构,其具有可调谐的和带隙的自旋极化和谷极化的倾斜狄拉克能带结构。从电子学的角度来看,1 T $^\prime$ -MoS $_2$是技术上最有前途的纳米材料之一,也是已经著名的过渡金属二硫属元素家族的新代表。所得到的修饰态强烈依赖于所施加的照射的极化,并反映了未照射的材料的初始低能哈密顿量的全部复杂性。我们已经计算和分析了所获得的电子修饰状态的线性和圆形类型的极化的施加场集中在其对称性,各向异性,倾斜和带隙,以及拓扑签名。由于圆偏振的敷料场也被称为诱导到一个新的状态与破缺的时间反演对称性和非零陈数的过渡,这些拓扑非平凡的阶段和它们之间的过渡的组合可以揭示一些真正独特的和早期未知的现象。
Reconstructing the wavefunction of magnetic topological insulators MnBi2Te4 and MnBi4Te7 using spin-resolved photoemission
Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory(斯坦福材料能源科学研究所,SLAC国家加速器实验室);Geballe Laboratory for Advanced Materials, Department of Physics and Applied Physics, Stanford University(斯坦福大学物理与应用物理系前沿材料盖博实验室);Department of Condensed Matter Physics, Weizmann Institute of Science(魏茨曼科学研究所凝聚态物理系);School of Physical Science and Technology, ShanghaiTech University(上海科技大学物质科学与技术学院);ShanghaiTech Laboratory for Topological Physics(上海拓扑物理实验室)
Measurement of the background in Auger-photoemission coincidence spectra (APECS) associated with inelastic or multi-electron valence band photoemission processes