Electronic Correlations in CoO2, the Parent Compound of Triangular Cobaltates

Abstract

A 59Co NMR study of CoO2, the x=0 end member of AxCoO2 (A = Na, Li...) cobaltates, reveals a metallic ground state, though with clear signs of strong electron correlations: low-energy spin fluctuations develop at wave vectors q different from 0 and a crossover to a Fermi-liquid regime occurs below a characteristic temperature T*~7 K. Despite some uncertainty over the exact cobalt oxidation state n this material, the results show that electronic correlations are revealed as x is reduced below 0.3. The data are consistent with NaxCoO2 being close to the Mott transition in the x -> 0 limit.

4 pages, submitted

References in corpus (18)

• Stretched Exponential Relaxation Arising from a Continuous Sum of Exponential Decays
• Cu NMR evidence for enhanced antiferromagnetic correlations around Zn impurities in YBa2Cu3O6.7
• Mott transition in Kagomé lattice Hubbard model
• Ferromagnetism, paramagnetism and a Curie-Weiss metal in an electron doped Hubbard model on a triangular lattice
• Doping effects on the electronic and structural properties of CoO2: An LSDA+U study
• 59Co NMR study of the Co states in superconducting and anhydrous cobaltates
• The Role of hybridization in NaxCoO2 and the Effect of Hydration
• Orbital Symmetry and Electron Correlation in Na_{x}CoO_2
• Magnetic susceptibility study of hydrated and non-hydrated NaxCoO2-yH2O single crystals
• Dynamical mean field study of the Mott transition in the half-filled Hubbard model on a triangular lattice
• Spin-Dynamics in the Carrier-Doped $S=1/2$ Triangular-Lattice of Na${}_x$CoO${}_2$-yH${}_2$O
• Na content dependence of superconductivity and the spin correlations in Na_{x}CoO_{2}\cdot 1.3H_{2}O
• Electronic Properties of the Hubbard Model on a Frustrated Triangular Lattice
• Stoichiometric oxygen content in NaxCoO2
• 17-O NMR studies of a triangular-lattice superconductor Na{x}CoO{2}yH{2}O
• Unconventional Superconductivity Induced by Quantum Critical Fluctuations in Hydrate Cobaltate Na${}_x$(H${}_3$O)${}_z$CoO${}_x\cdot$ $y$H${}_2$O -- Relationship between Magnetic Fluctuations and the Superconductivity Revealed by a Co Nuclear Quadrupole Resonance --
• Electron-boson mode coupling and the pseudogap of Na${}_x$CoO${}_2$ by infrared spectroscopy
• Na${}_x$CoO${}_2$ in the x -> 0 Regime: Coupling of Structure and Correlation effects

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• Electrochemical synthesis and properties of CoO2, the x = 0 phase of the AxCoO2 systems (A = Li, Na)
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