@article{7f798e0e3d834b46af2adec1bffdb860,
title = "Observation of momentum-dependent charge excitations in hole-doped cuprates using resonant inelastic x-ray scattering at the oxygen K edge",
abstract = "We investigate electronic excitations in La2-x(Br,Sr)xCuO4 using resonant inelastic x-ray scattering (RIXS) at the oxygen K edge. RIXS spectra of the hole-doped cuprates show clear momentum dependence below 1 eV. The broad spectral weight exhibits positive dispersion and shifts to higher energy with increasing hole concentration. Theoretical calculation of the dynamical charge structure factor on oxygen orbitals in a three-band Hubbard model is consistent with the experimental observation of the momentum and doping dependence, and therefore the momentum-dependent spectral weight is ascribed to intraband charge excitations which have been observed in electron-doped cuprates. Our results confirm that the momentum-dependent charge excitations exist on the order of the transfer energy (t), and the broad spectral line shape indicates damped and incoherent character of the charge excitations at the energy range in the doped Mott insulators.",
author = "Kenji Ishii and Takami Tohyama and Shun Asano and Kentaro Sato and Masaki Fujita and Shuichi Wakimoto and Kenji Tustsui and Shigetoshi Sota and Jun Miyawaki and Hideharu Niwa and Yoshihisa Harada and Jonathan Pelliciari and Yaobo Huang and Thorsten Schmitt and Yoshiya Yamamoto and Jun'Ichiro Mizuki",
note = "Funding Information: The authors would like to thank H. Yamase and A. Greco for invaluable discussions and M. Dantz for experimental assistance at the ADRESS beamline. This work was carried out under the Inter-University Cooperative Research Program of the Institute for Materials Research, Tohoku University (Proposal No. 16K0048), and the joint research in the Synchrotron Radiation Research Organization and the Institute for Solid State Physics (ISSP), the University of Tokyo. The synchrotron radiation experiments at the Paul Scherrer Institut were performed at the ADRESS beamline of the Swiss Light Source, and those at SPring-8 were carried out at the BL07LSU with the approval of the Japan Synchrotron Radiation Research Institute (JASRI) (Proposals No. 2016A7510 and No. 2015A7484). Numerical works were supported by a post-K computer project: Creation of new functional devices and high-performance materials to support next-generation industries (CDMSI) and by HPCI Strategic Programs for Innovative Research (SPIRE) (hp160099 and hp160222). The numerical calculation was carried out at the K Computer and ISSP, the University of Tokyo. This work was financially supported by JSPS KAKENHI Grants No. 25400333, No. 26287079, No. 16H02125, No. 16H04004, and No. 15H03553. J.P. and T.S. acknowledge financial support through the Dysenos AG by Kabelwerke Brugg AG Holding, Fachhochschule Nordwestschweiz, and the Paul Scherrer Institut. J.P. also acknowledges financial support by the Swiss National Science Foundation Early Postdoc.Mobility fellowship Project No. P2FRP2_171824. Publisher Copyright: {\textcopyright} 2017 American Physical Society.",
year = "2017",
month = sep,
day = "22",
doi = "10.1103/PhysRevB.96.115148",
language = "English",
volume = "96",
journal = "Physical Review B",
issn = "2469-9950",
publisher = "American Physical Society",
number = "11",
}