The role of pair-transfer interaction in alkali-metal-doped C_(60)

摘要

We study the role of pair-transfer interaction in alkali-metal-doped C_(60), A_xC_(60) where A is alkali metal. This interaction is originated in the dynamic Jahn-Teller effect caused by the coupling of the conduction electrons to the intramolecular phonons. It is found that the pair-transfer interaction induces an attractive interaction between the conduction electrons and thus results in the superconductivity in A_3C_(60) when the interaction dominates the intraorbital repulsion between the conduction electrons. The equivalence of the present mechanism to the Suhl-Kondo mechanism in multiple-band superconductors is pointed out.