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Nature of Correlated Motion of Electrons in the Parent Cobaltate Superconductors

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

Recently discovered class of cobaltate superconductors (Na0.3CoO2.nH2O) is a novel realization of interacting quantum electron systems in a triangular network with low-energy degrees of freedom. We employ angle-resolved photoemission spectroscopy to uncover the nature of microscopic electron motion in the parent superconductors for the first time. Results reveal a large hole-like Fermi surface (consistent with Luttinger theorem) generated by the crossing of super-heavy quasiparticles. The measured quasiparticle parameters collectively suggest a two orders of magnitude departure from the conventional Bardeen-Cooper-Schrieffer electron dynamics paradigm and unveils cobaltates as a rather hidden class of relatively high temperature superconductors.

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M. Z. Hasan, D. Qian, Y. Li, A. V. Fedorov, Y. -D. Chuang, A. P. Kuprin, M. L. Foo, R. J. Cava. 2005-01-30. Nature of Correlated Motion of Electrons in the Parent Cobaltate Superconductors. https://doi.org/10.1016/j.aop.2006.03.008

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