Elucidating the impact of strong electronic interactions on the collective excitations of metallic systems has been of longstanding interest, mainly due to the inadequacy of the random phase approximation (RPA) in the strongly correlated regime. Here, we adopt our newly developed radial Kotliar and Ruckenstein slave boson representation to analyze the charge excitation spectrum of a Hubbard model, extended with long range interactions. Working on the face centered cubic lattice, at half filling, and in different coupling regimes ranging from uncorrelated to the metal-to-insulator transition, we compare our results to conventional RPA as a benchmark. We focus on the influence of the local and long range couplings on the particle-hole excitation continuum and the plasmon and upper Hubbard band collective modes. Beyond the weak coupling regime, we find numerous quantitative and even qualitative discrepancies between our method and standard RPA. Our work thus deepens the understanding of charge collective modes in correlated systems, and lays the foundations for future studies of a broad series of materials.
Strongly correlated model of acousticlike plasmons persisting across the phase diagram of cuprate superconductors
Facultad de Ciencias Exactas, Ingeniería y Agrimensura (UNR-CONICET)（罗萨里奥大学理、工和测量学院（罗萨里奥大学-阿根廷国家科学技术研究委员会））；Research Center of Materials Nanoarchitectonics (MANA), National Institute for Materials Science (NIMS)（物质纳米结构研究中心（MANA），日本国立材料研究所（NIMS））；Max-Planck-Institute for Solid State Research（马克斯·普朗克固体研究所）；Instituto de Física Rosario (UNR-CONICET)（罗萨里奥物理研究所（罗萨里奥大学-阿根廷国家科学技术研究委员会））
Interfacial Strain Modulated Correlated Plasmons in La1.85Sr0.15CuO4 and Their Role in High-temperature Superconductivity
Shanghai University（上海大学）；Agency for Science, Technology and Research (A*STAR)（科学技术研究局）；Soochow University（苏州大学）；Anhui University（安徽大学）；National University of Singapore（新加坡国立大学）
Observation of correlated plasmons in low-valence nickelates
Brookhaven National Laboratory（布鲁克海文国家实验室）；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北京国家实验室）；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）；National Synchrotron Light Source II, Brookhaven National Laboratory（布鲁克海文国家实验室第二代同步辐射光源）；Shanghai Advanced Research in Physical Sciences (SHARPS)（上海物理科学研究前沿中心）
Dynamical screening effects in correlated materials: plasmon satellites and spectral weight transfers from a Green's function ansatz to extended dynamical mean field theory
Optical spectroscopy of plasmons and excitons in cuprate superconductors
介绍了层状高温超导体中的集体模。本文对Anderson提出的当超导体中U（1）规范对称性破缺时，在超导体中运动的光子变得有质量的机制进行了实验论证。利用费雷尔-廷卡姆求和定则，我们证明了光子质量与凝聚体的光谱权有一个简单的关系。各种形式的约瑟夫森等离子体可以存在于单层和双层的uprates。在双层铜氧化物中，可以观察到横向光学等离子体模式作为c轴光学电导率的峰值。这种模式出现作为一个后果的存在两个不同的固有的约瑟夫森耦合之间的CuO 2层。它与集体振荡密切相关，集体振荡对应于两种凝聚体的相对相位的小波动，这是由A. J. Leggett在1966年预测的具有两个载流子带的超导体。给出了一个描述的光学数据的高Tc铜酸盐证明这些和类似的集体模式的存在。
Columbia University（哥伦比亚大学）；University of California at San Diego（加州大学圣地亚哥分校）；Instituto de Ciencia de Materiales de Madrid ICMM-CSIC（马德里材料科学研究所 ICMM-CSIC）；Stony Brook University（石溪大学）；Brookhaven National Laboratory（布鲁克海文国家实验室）；Max Planck Institute for Structure and Dynamics of Matter（马克斯·普朗克物质结构与动力学研究所）；The Flatiron Institute（平顿研究所）；Universidad del País Vasco UPV/EHU（巴斯克地区大学）；Pennsylvania State University（宾夕法尼亚州立大学）
Visualizing a Terahertz Superfluid Plasmon in a Two-Dimensional Superconductor
Massachusetts Institute of Technology（麻省理工学院）；Harvard University（哈佛大学）；Max Planck for the Structure and Dynamics of Matter（马普物质结构与动力学研究所）；Max Planck Institute for the Physics of Complex Systems（马普复杂系统物理研究所）；Center for Computational Quantum Physics (CCQ), Flatiron Institute（平顿研究院计算量子物理中心）；Department of Condensed Matter Physics and Materials Science, Brookhaven National Laboratory（布鲁克海文国家实验室凝聚态物理与材料科学系）
