Motivated by the mid-infrared scenario for high-temperature superconductivity proposed by Leggett, the effects of Umklapp processes on the density-density correlation function in the presence of long-range Coulomb interaction have been investigated on a microscopic model. We show that because Umklapp processes enable scatterings that conserve total momentum only up to $n\vec{K}$, where $n$ is an integer and $\vec{K}$ is the reciprocal wave vector, significant amounts of spectral weight in the plasmonic excitations at long wavelength are transferred into lower frequency around mid-infrared regime. We further find that regardless of the gap symmetry, superconductivity generally suppresses the Umklapp scatterings due to the formation of the electron pairing. This suppression is unique for the superconductivity due to the interplay between electron pairing and the odd parity of the matrix elements associated with Umklapp channels, which usually does not occur in other known competing orders. Specific predictions for the experimental signatures in optical conductivity and electron energy loss spectroscopy (EELS) will be discussed.
Correlation between the strength of low-temperature T-linear normal-state resistivity and $T_{\rm c}$ in overdoped electron-doped cuprate superconductors
本文在动能驱动超导框架内，揭示了过掺杂电子掺杂型铜氧化物超导体中由自旋激发同时介导的电子umklapp散射与电子配对，自然导致了低温T线性正常态电阻率强度与超导转变温度$T_{\ m c}$之间的内在关联。
Superconductivity-Enabled Conversion of Ferromagnetic Resonance into Standing Spin Waves
HSE University（高等经济大学）；Russian Quantum Center（俄罗斯量子中心）；Moscow Institute of Physics and Technology（莫斯科物理技术学院）；Physical-Technical Institute, Vernadsky Crimean Federal University（维尔纳茨克克里米亚联邦大学物理技术研究所）；Centre for Advanced Mesoscience and Nanotechnology, Moscow Institute of Physics and Technology（莫斯科物理技术学院先进介观科学与纳米技术中心）；Lomonosov Moscow State University（莫斯科罗蒙诺索夫国立大学）
Strong Correlations and Superconductivity in the Supermoiré Lattice
Institute of Physics, Ecole Polytechnique Fédérale de Lausanne（洛桑联邦理工学院物理研究所）；Dahlem Center for Complex Quantum Systems and Fachbereich Physik, Freie Universität Berlin（柏林自由大学复杂量子系统达勒姆中心及物理系）；Research Center for Functional Materials, National Institute for Materials Science（国立材料科学研究所功能材料研究中心）；International Center for Materials Nanoarchitectonics, National Institute for Materials Science（国立材料科学研究所国际纳米材料架构中心）；National High Magnetic Field Laboratory（国家高磁场实验室）；Department of Physics, Florida State University（佛罗里达州立大学物理系）；Center for Quantum Science and Engineering, Ecole Polytechnique Fédérale de Lausanne（洛桑联邦理工学院量子科学与工程中心）
Spectroscopic Studies of two-dimensional Superconductivity
Tsinghua University（清华大学）；Frontier Science Center for Quantum Information（量子信息前沿科学中心）；Beijing Academy of Quantum Information Sciences（北京量子信息科学研究院）；Southern University of Science and Technology（南方科技大学）
Competing incommensurability, electronic correlations, and superconductivity in a hybrid transition metal dichalcogenide
Weizmann Institute of Science（魏茨曼科学研究所）；University of Hamburg（汉堡大学）；Bar Ilan University（巴伊兰大学）；The Pennsylvania State University（宾夕法尼亚州立大学）；Technion - Israel Institute of Technology（以色列理工学院）；Goethe Universität Frankfurt（法兰克福歌德大学）
Granular aluminum induced superconductivity in germanium for hole spin-based hybrid devices
ISTA, Institute of Science and Technology Austria（奥地利科学技术研究所）；Quantum Advanced Research Center (QuARC), Consejo Superior de Investigaciones Científicas (CSIC)（西班牙高等科学研究理事会量子先进研究中心）；Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Científicas (CSIC)（西班牙高等科学研究理事会马德里材料科学研究所）
Realization of Air-Stable Two-Dimensional Superconductor Nb2Pd3Te5 With Quasi-One-Dimensional Pair Density Modulation
Beijing National Center for Condensed Matter Physics and Institute of Physics, Chinese Academy of Sciences（中国科学院物理研究所北京凝聚态物理国家研究中心）；School of Physical Sciences, University of Chinese Academy of Sciences（中国科学院大学物理科学学院）；New Cornerstone Science Laboratory, Department of Physics, The University of Hong Kong（香港大学物理系新基石科学实验室）
