Identifying the pairing symmetry in sodium cobalt oxide by Andreev edge states

Abstract

We study the Andreev edge states with different pairing symmetries and boundary topologies on semi-infinite triangular lattice of Na_xCoO_2.yH_2O. A general mapping from the two dimensional lattice to the one dimensional tight-binding model is developed. It is shown that the phase diagram of the Andreev edge states depends on the pairing symmetry and also the boundary topology. Surprisingly, the structure of the phase diagram crucially relies on the nodal points on the Fermi surface and can be explained by an elegant gauge argument. We compute the momentum-resolved local density of states near the edge and predict the hot spots which are measurable in Fourier-transformed scanning tunneling spectroscopy.

arXiv comment12 pages, 17 figures

References in corpus (35)

• Imaging Quasiparticle Interference in Bi2Sr2CaCu2O8+d
• Charge-ordering, commensurability and metallicity in the phase diagram of layered Na(x)CoO(2)
• Commensurability, excitation gap and topology in quantum many-particle systems on a periodic lattice
• Superconductivity Phase Diagram of Na(x)CoO(2).1.3H(2)O
• 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
• Coherence-Incoherence and Dimensional Crossover in Layered Strongly Correlated Metals
• Unconventional Superconductivity and Electron Correlations in Cobalt Oxyhydrate Na${}_{0.35}$CoO${}_2$$\cdot y$H${}_2$O
• Doped t-J Model on a Triangular Lattice: Possible Application to Na${}_x$CoO${}_2\cdot y$H${}_2$0 and Na${}_{1-x}$TiO${}_2$
• Thermodynamic and Transport Measurements on Superconducting Na_xCoO_2 + yH_2O Single Crystals Prepared by Electrochemical De-intercalation
• Unconventional Superconductivity and Nearly Ferromagnetic Spin Fluctuations in Na${}_x$CoO${}_2$$\cdot y$H${}_2$O
• Possible spin triplet superconductivity in Na${}_x$CoO${}_2\cdot y$H${}_2$0
• Ferromagnetic fluctuation and possible triplet superconductivity in Na_xCoO_2*yH_2O: Fluctuation-exchange study of multi-orbital Hubbard model
• Possible spin-triplet $f$-wave pairing due to disconnected Fermi surfaces in Na${}_x$CoO${}_2\cdot y$H${}_2$O
• Superconductivity in Na_xCoO_2yH_2O by charge fluctuation
• A critical assessment of the pairing symmetry in NaxCoO2.yH2O
• Spin singlet pairing in the superconducting state of NaxCoO2\cdot1.3H2O: evidence from a ^{59}Co Knight shift in a single crystal
• Possibility of f-wave spin-triplet superconductivity in the CoO superconductor: a case study on a 2D triangular lattice in the repulsive Hubbard model
• Symmetry of the superconducting order parameter in frustrated systems determined by the spatial anisotropy of spin correlations
• Angle-resolved photoemission study of cobalt oxide superconductor NaxCoO2.yH2O : Observation of the Fermi surface
• Evidence of nodal superconductivity in Na_0.35CoO2-1.3H_2O: a specific heat study
• Possible unconventional superconductivity in Na${}_x$CoO${}_2$yH${}_2$O probed by $\mu$SR
• 59Co-NMR Knight Shift of Aligned Crystals and Polycrystalline Samples of Superconducting Na0.3CoO2.1.3H2O
• Na content dependence of superconductivity and the spin correlations in Na_{x}CoO_{2}\cdot 1.3H_{2}O
• Muon Spin Relaxation Measurements in Na_xCoO_2*yH_2O
• Possible Spin-triplet Superconductivity in NaxCoO2yH2O - 59Co NMR Study
• Correlation Effects of Single-Wall Carbon Nanotubes in Weak Coupling
• Edge-currents in superconductors with a broken time-reversal symmetry
• Anisotropic Behavior of Knight Shift in Superconducting State of Na_xCoO_2yH_2O
• Correlation between Superconducting Transition Temperature $T_c$ and Increase of Nuclear Spin-Lattice Relaxation Rate Devided by Temperature $1/T_{1}T$ at $T_c$ in the Hydrate Cobaltate Na${}_x$CoO${}_2\cdot y$H${}_2$O
• Vortex State in Na_xCoO_2.yH_2O: p_x\pm ip_y-wave versus d_{x^2-y^2}\pm id_{xy}-wave Pairing
• Andreev Edge State on Semi-Infinite Triangular Lattice: Detecting the Pairing Symmetry in Na_0.35CoO_2.yH_2O
• Midgap States and Generalized Supersymmetry in Semi-infinite Nanowires
• Nuclear Spin Relaxation Rate of Disordered $p_x+i{p}_y$-wave Superconductors
• Ground-State Degeneracy of Correlated Insulators with Edges

Cited by in corpus (2)

• Shiba chains of scalar impurities on unconventional superconductors
• Andreev bound states in iron pnictide superconductors