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Low-lying electronic structure of doped triangular cobaltates

A. P. Kuprin·D. Qian·Y. -D. Chuang·M. Foo·R. J. Cava·M. Z. Hasan
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Abstract

We report detailed Fermi surface topology and quasiparticle dynamics of the host cobaltate Na0.7CoO2. A direct mapping of the Fermi surface is carried out by angle-resolved photoemission spectroscopy (ARPES). Fermi surface at temperature 16K is a hole-pocket centered around the Gamma-point. The highly correlated nature of the electron liquid is evidenced from strong on-site Coulomb interaction seen through a valence satellite and via renormalization of the quasiparticle dispersion. The quasiparticle exhibits spectral coherence only below 150K which includes the non-Fermi liquid regime.

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A. P. Kuprin, D. Qian, Y. -D. Chuang, M. Foo, R. J. Cava, M. Z. Hasan. 2006-05-11. Low-lying electronic structure of doped triangular cobaltates. https://doi.org/10.1016/j.jpcs.2005.10.158

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