Complete d-Band Dispersion Relation in Sodium Cobaltates

ORAL

Abstract

We utilize fine-tuned polarization selection coupled with excitation-energy variation of photoelectron signal to image the complete d-band dispersion relation in sodium cobaltates. A hybridization gap anticrossing is observed along the Brillouin zone corner and the full quasiparticle band is found to emerge as a many-body entity lacking a pure orbital polarization. At low dopings, the quasiparticle bandwidth (Fermion scale, many- body EF $\sim$ 0.25 eV) is found to be smaller than most known oxide metals. The low-lying density of states is found to be in agreement with bulk-sensitive thermodynamic measurements for nonmagnetic dopings where the 2D Luttinger theorem is also observed to be satisfied.

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Authors

  • Dong Qian

    • Department of Physics, Princeton University
    • Princeton University

  • L. Wray

    • Princeton University

  • D. Hsieh

    • Princeton University

  • L. Viciu

    • Princeton University

  • R.J. Cava

    • Princeton University

  • J.L. Luo

    • Institute of Physics, Chinese Academy of Sciences

  • D. Wu

    • Institute of Physics, Chinese Academy of Sciences

  • N.L. Wang

    • Institute of Physics, Chinese Academy of Sciences

  • M.Z. Hasan

    • Department of Physics, Princeton University
    • Princeton University