Exotic s-wave superconductivity in alkali-doped fullerides.
TL;DR: In this article, the electron-phonon coupling and electron-electron interactions are used to realize an unconventional s-wave superconductivity in the alkali-doped fullerides.
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Abstract: Alkali-doped fullerides (A3C60 with A = K, Rb, Cs) show a surprising phase diagram, in which a high transition-temperature (Tc) s-wave superconducting state emerges next to a Mott insulating phase as a function of the lattice spacing. This is in contrast with the common belief that Mott physics and phonon-driven s-wave superconductivity are incompatible, raising a fundamental question on the mechanism of the high-Tc superconductivity. This article reviews recent ab initio calculations, which have succeeded in reproducing comprehensively the experimental phase diagram with high accuracy and elucidated an unusual cooperation between the electron-phonon coupling and the electron-electron interactions leading to Mott localization to realize an unconventional s-wave superconductivity in the alkali-doped fullerides. A driving force behind the exotic physics is unusual intramolecular interactions, characterized by the coexistence of a strongly repulsive Coulomb interaction and a small effectively negative exchange interaction. This is realized by a subtle energy balance between the coupling with the Jahn-Teller phonons and Hund's coupling within the C60 molecule. The unusual form of the interaction leads to a formation of pairs of up- and down-spin electrons on the molecules, which enables the s-wave pairing. The emergent superconductivity crucially relies on the presence of the Jahn-Teller phonons, but surprisingly benefits from the strong correlations because the correlations suppress the kinetic energy of the electrons and help the formation of the electron pairs, in agreement with previous model calculations. This confirms 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.
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References
Superconductivity in Doped Fullerenes
TL;DR: Carbon 60 is a fascinating and arrestingly beautiful molecule with 12 pentagonal and 20 hexagonal faces symmetrically arrayed in a soccer-ball-like structure that belongs to the icosahedral point group Ih as mentioned in this paper.
Strongly correlated superconductivity.
Massimo Capone,Michele Fabrizio,Michele Fabrizio,Claudio Castellani,Erio Tosatti,Erio Tosatti +5 more
TL;DR: In this paper, the authors examined a dynamical mean-field solution of a model for electron-doped fullerenes that shows how strong correlations can indeed enhance superconductivity close to the Mott transition and argued that the mechanism responsible for this enhancement could be common to a wider class of strongly correlated models, including those for cuprate superconductors.
Consideration of the mechanism of superconductivity in fullerenes: Beyond migdal's theorem and the dynamic Coulomb effect
TL;DR: In this paper, a vertex corrections up to infinite order in the calculation of the superconducting transition temperature T c for the alkali-metal-doped fullerenes were presented.
On the thermodynamic properties of the Rb3C60 superconductor
TL;DR: In this paper, the thermodynamic properties of the superconducting state in Rb3C60 fulleride have been studied in the framework of the Migdal-Eliashberg approach.
Double-expansion impurity solver for multiorbital models with dynamically screened $U$ and $J$
TL;DR: In this article, a continuous-time Monte Carlo impurity solver for multiorbital impurity models is presented, which combines a strong coupling hybridization expansion and a weak coupling expansion in the Hund's coupling parameter.