Pairing associated with a single quantum critical energy in superconducting electron-doped cuprates

ORAL

Abstract

Though a comprehensive study of magnetotransport on electron-doped La$_{2-x}$Ce$_{x}$CuO$_{4}$ thin films, we show that an envelope of spin fluctuations yielding non Fermi liquid behavior ($\rho =\rho _{0}$ +AT) surrounds the superconducting dome in the overdoped region (x =0.15 to 0.21). This behavior survives to zero temperature over a range of fields exceeding the upper critical field. For example, the resistivity of x = 0.15 is linear in temperature over three decades down to 20 mK at 7.5 T. We demonstrate that all of the relevant energy scales in this system: those determining superconducting pairing, spin correlations, and the Fermi liquid metallic state, emanate from one common critical point at the end of the superconducting dome. These observations suggest that the superconductivity pairing is associated with spin fluctuations and with a single quantum critical energy in electron-doped cuprates. This work was partially supported by NSF-DMR 0653535.

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Authors

  • Kui Jin

    Center for Nanophysics \& Advanced Materials and Department of Physics, University of Maryland, College Park, MD 20742, USA

  • Nick Butch

    Center for Nanophysics and Advanced Materials, U. of Maryland, Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland, College Park, MD, Center for Nano Physics and Advanced Materials, Department of Physics, University of Maryland, College Park, MD, Department of Physics, University of Maryland, Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland, College Park, University of Maryland, Center for Nanophysics \& Advanced Materials and Department of Physics, University of Maryland, College Park, MD 20742, USA

  • Kevin Kirshenbaum

    Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland, College Park, MD, Center for Nanophysics \& Advanced Materials and Department of Physics, University of Maryland, College Park, MD 20742, USA, University of Maryland

  • Paul Bach

    Center for Nanophysics and Advanced Materials, University of Maryland, Center for Nanophysics \& Advanced Materials and Department of Physics, University of Maryland, College Park, MD 20742, USA

  • Johnpierre Paglione

    Center for Nanophysics and Advanced Materials, U. of Maryland, University of Maryland, Center for Nanophysics and Advanced Materials, Department of Physics, University of Maryland, College Park, MD, Center for Nano Physics and Advanced Materials, Department of Physics, University of Maryland, College Park, MD, Department of Physics, University of Maryland, University of Maryland at College Park, Center for Nanophysics \& Advanced Materials and Department of Physics, University of Maryland, College Park, MD 20742, USA

  • Richard Greene

    Center for Nanophysics \& Advanced Materials and Department of Physics, University of Maryland, College Park, MD 20742, USA