Appearance of Universal Metallic Dispersion in a Doped Mott Insulator

ORAL

Abstract

Under strong electronic correlations the parent compounds of all cuprate high-temperature superconductors assume the so-called Mott-Hubbard insulating state. By what routes these insulators accomplish the miraculous transformation into superconductors with the addition of electrons or holes is a question of intense current interest. In this study we consider the classic superconductor La$_{2-x}$Sr$_x$CuO$_4$ (LSCO) over the wide doping range of $x=0.03-0.30$, delineating how the electronic spectrum evolves with doping for binding energies extending to several hundred meV's. Our analysis indicates that this Mott insulator contains `nascent' or `preformed' metallic states, which develop finite spectral weight with doping, but otherwise undergo relatively little change in dispersion over a wide doping range. Our findings challenge existing theoretical scenarios for cuprates. Work supported in part by the USDOE.

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Authors

  • Hsin Lin

    • Northeastern U.
    • Northeastern University

  • S. Sahrakorpi

    • Northeastern U.

  • R.S. Markiewicz

    • Northeastern U.

  • M. Lindroos

    • Northeastern U. and TUT Finland

  • X.J. Zhou

    • Stanford U. and LBNL

  • T. Yoshida

    • U. of Tokyo

  • W.L. Yang

    • Stanford U. and LBNL

  • T. Kakeshita

    • U. of Tokyo

  • H. Eisaki

    • Stanford U. and U. of Tokyo

  • S. Uchida

    • U. of Tokyo

  • Seiki Komiya

    • CRIEPI Japan

  • Yoichi Ando

    • Osaka U.

  • F. Zhou

    • Chinese Acad. of Sci.

  • Z.X. Zhao

    • Chinese Acad. of Sci.

  • T. Sasagawa

    • Stanford U. and TIT Japan

  • A. Fujimori

    • U. of Tokyo

  • Z. Hussain

    • LBNL

  • Z.-X. Shen

    • Stanford U. and LBNL

  • A. Bansil

    • Northeastern U.