Repulsive interaction helps superconductivity in fullerides

  title={Repulsive interaction helps superconductivity in fullerides},
  author={Satoshi Yamazaki and Y. Kuramoto},
  journal={Bulletin of the American Physical Society},
A repulsive interaction model of superconductivity (SC) is studied for tight-binding models with three-fold degenerate molecular orbitals. Taking a weak-coupling approach, we derive dimensionless coupling constants for various symmetries of SC pairs. In addition to anisotropic SC pairs, the s-wave (\(A_{g}\)) pairing can also be formed. With the purely repulsive interaction, however, the \(A_{g}\) pair is not the most stable in both bcc and fcc lattices. The most stable SC pair for the bcc… 
4 Citations
Cooperation between Coulomb and Electron-Phonon Interactions in Fulleride Superconductors
We study cooperative effects between Coulomb and electron-phonon interactions in Alkali-metal doped fullerides (A3C60) using multiorbital Hubbard-Holstein model. By taking the random phase
Exotic s-wave superconductivity in alkali-doped fullerides.
Recent ab initio calculations confirm that the alkali-doped fullerides are a new type of unconventional superconductors, where the unusual synergy between the phonons and Coulomb interactions drives the high-Tc superconductivity.
Introduction to Superconductivity in Alkali-Doped Fullerides
In this chapter, we give an introduction to the superconductivity in alkali-doped fullerides, which show the highest transition temperature (\(T_\mathrm{c}\)) among molecular solids. We review
Nonempirical Calculation of Superconducting Transition Temperatures in Light-Element Superconductors.
This study obtains a unified view of the high-Tc superconductivity and the Mott-Hubbard transition in the fullerides and demonstrates that the combination of density functional theory and dynamical mean field theory with the ab initio downfolding scheme for electron-phonon coupled systems works successfully.


Superconductivity in fullerides
Experimental studies of the superconductive properties of fullerides are briefly reviewed. Theoretical calculations of the electron-phonon coupling, in particular for the intramolecular phonons, are
Near-degeneracy of several pairing channels in multiorbital models for the Fe pnictides
Weak-coupling approaches to the pairing problem in the iron pnictide superconductors have predicted a wide variety of superconducting ground states. We argue here that this is due both to the
Superconductivity in the repulsive Hubbard model: An asymptotically exact weak-coupling solution
We study the phase diagram of the Hubbard model in the limit where $U$, the onsite repulsive interaction, is much smaller than the bandwidth. We present an asymptotically exact expression for
Multi-orbital Analysis on the Superconductivity in NaxCoO2 yH2O
We preform a multi-orbital analysis on the novel superconductivity in Na x CoO 2 · y H 2 O. We construct a three-orbital model which reproduces the band structure expected from the LDA calculation.
Roles of Multipoles and Excitons in Superconductor PrOs4Sb12 with Th Symmetry
A possibility of exciton-mediated mechanism is studied to describe the superconductivity in a Pr skutterudite PrOs 4 Sb 12 . In this compound the low-lying crystal-field states of Pr form a
Orbital-fluctuation-mediated superconductivity in iron pnictides: analysis of the five-orbital Hubbard-Holstein model.
In iron pnictides, the moderate electron-phonon interaction due to the Fe-ion oscillation can induce the critical d-orbital fluctuations, which give rise to the strong pairing interaction for the s-wave superconducting (SC) state without sign reversal (s(++)-wave state), consistent with experimentally observed robustness of superconductivity against impurities.
Modelling the unconventional superconducting properties of expanded A3C60 Fullerides
The trivalent alkali fullerides A$_3$C$_{60}$, where C$_{60}$ are a well established family of molecular superconductors. The electron pairing has s-wave symmetry and is due to standard
The Disorder-Free Non-BCS Superconductor Cs3C60 Emerges from an Antiferromagnetic Insulator Parent State
In Cs3C60, where the molecular valences are precisely assigned, the superconducting state at 38 kelvin emerges directly from a localized electron antiferromagnetic insulating state with the application of pressure, with a dependence of the transition temperature on pressure-induced changes of anion packing density that is not explicable by Bardeen-Cooper-Schrieffer (BCS) theory.
Strong superconductivity with local Jahn-Teller phonons in C60 solids.
It is demonstrated that the Jahn-Teller phonons create a local (intramolecular) pairing which is surprisingly resistant to the Coulomb repulsion, despite the weakness of retardation in these low-bandwidth systems.
Cooperative effects of Coulomb and electron-phonon interactions in the two-dimensional 16-band d-p model for iron-based superconductors
We study the electronic states and the superconductivity in the two-dimensional 16-band d-p model coupled with A1g, B1g and Eg local phonons and obtain the rich phase diagram including the magnetic,