Study of the triangular lattice tV model near x=1/3

Abstract

We study extended Hubbard model on a triangular lattice near doping $x=1/3$, which may be relevant for the recently discovered superconductor Na${}_x$CoO${}_2\cdot y$H${}_2$O. By generalizing this model to $N$ fermionic species, we formulate a meanfield description in the limit of large $N$. In meanfield, we find two possible phases: a renormalized Fermi liquid and a $\rt3rt3$ charge density wave state. The transition between the two phases is driven by increasing the nearest neighbor repulsion and is found to be first order for doping $x=1/3$, but occurs close to the point of the local instability of the uniform liquid. We also study fluctuations about the uniform meanfield state in a systematic 1/N expansion, focusing on the residual interaction of quasiparticles and possible superconducting instabilities due to this interaction. Upon moving towards the CDW instability, the increasing charge fluctuations favor a particular $f$-wave triplet state. (This state was recently discussed by Tanakaet al, cond-mat/0311266). We also report a direct Gutzwiller wavefunction study of the spin-1/2 model.

9 pages, 5 figures

References in corpus (6)

• An Electronic Model for $Co{O}_2$ layer based systems: Chiral RVB metal and Superconductivity
• Superconductivity in CoO${}_2$ Layers and the Resonating Valence Bond Mean Field Theory of the Triangular Lattice t-J model
• Doped t-J Model on a Triangular Lattice: Possible Application to Na${}_x$CoO${}_2\cdot y$H${}_2$0 and Na${}_{1-x}$TiO${}_2$
• Superconducting states in frustrating t-J model: A model connecting high-$T_c$ cuprates, organic conductors and Na${}_x$CoO${}_2$
• Instabilities of interacting electrons on the triangular lattice
• 59Co-NMR Knight Shift of the Superconducting NaxCoO2.yH2O

Cited by in corpus (37)

• Fermi surface evolution and Luttinger theorem in Na${}_x$CoO${}_2$: a systematic photoemission study
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• Low-lying quasiparticle states and hidden collective charge instabilities in parent cobaltate superconductors (NaxCoO2)
• Novel Charge Order and Superconductivity in Two-Dimensional Frustrated Lattice at Quarter Filling
• Complete d-Band Dispersion and the Mobile Fermion Scale in NaxCoO2
• Spin singlet pairing in the superconducting state of NaxCoO2\cdot1.3H2O: evidence from a ^{59}Co Knight shift in a single crystal
• Spin-triplet $f$-wave pairing in twisted bilayer graphene near 1/4 filling
• Doped Mott Insulators in the Triangular Lattice Hubbard Model
• Quasiparticle coherence and the nature of the metal-insulator phase transition in Na${}_x$CoO${}_2$
• Extended Hubbard model: Charge Ordering and Wigner-Mott transition
• Spin-Dynamics in the Carrier-Doped $S=1/2$ Triangular-Lattice of Na${}_x$CoO${}_2$-yH${}_2$O
• Nodal $d+id$ pairing and topological phases on the triangular lattice: unconventional superconducting state of Na${}_x$CoO${}_2\cdot y$H${}_2$O
• Charge order and superconductivity in a two-dimensional triangular lattice at n=2/3
• Anomalous electronic Raman scattering in Na_xCoO_2 H_2O
• Large-N expansion based on the Hubbard operator path integral representation and its application to the t-J model II. The case for finite $J$
• Non-Fermi liquid behavior in nearly charge ordered layered metals
• Competition between charge and spin order in the $t-U-V$ extended Hubbard model on the triangular lattice
• Correlation-driven charge order in a frustrated two-dimensional atom lattice
• Novel phase diagram of superconductor NaxCoO2-yH2O in a 75 % relative humidity
• Textured electronic states of the triangular lattice Hubbard model and Na${}_x$CoO${}_2$
• Crossover between electron-electron and electron-phonon mediated pairing on the Kagome lattice
• Long-Period Charge Correlations in Charge-Frustrated Molecular theta-(BEDT-TTF)2X
• Resonating Valence Bond Theory of Superconductivity for Dopant Carriers: Application to the Cobaltates
• Cooperative effect of phonons and electronic correlations for superconductivity in cobaltates
• Spin exchange and superconductivity in a $t-J^{\prime }-V$ model for two-dimensional quarter-filled systems
• s-wave Superconductivity due to Suhl-Kondo Mechanism in Na${}_x$CoO${}_2\cdot y$H${}_2$O: Effect of Coulomb Interaction and Trigonal Distortion
• Electron-phonon interaction dressed by electronic correlations near charge ordering as the origin for superconductivity in cobaltates
• Superconductivity in doped triangular Mott insulators: the roles of parent spin backgrounds and charge kinetic energy
• Dynamical magnetic susceptibility in the lamellar cobaltate superconductor Na_xCoO_2$\cdot y$H_2O
• Density-matrix based numerical methods for discovering order and correlations in interacting systems
• Pressure dependence of the superconducting transition and electron correlations in Na_xCoO_2 \cdot 1.3H_2O
• Charge order and phonon renormalizations: Possible implications for cobaltates
• One-particle spectral properties of the t-J-$V$ model on the triangular lattice near charge order
• Ground state and spectral properties across a Charge Density Wave transition in a triangular-lattice spinless Fermion model
• Evolution of electron Fermi surface with doping in cobaltates
• Absence of spin susceptibility decrease in a bulk organic superconductor with triangular lattice