Unified Model for Superconductivity in Graphite Intercalation Compounds: Prediction of Optimum Tc and Suggestion for Its Realization

Based on the model that was successfully applied to KC 8 , RbC 8 , and CsC 8 in 1982, we have calculated the superconducting transition temperature T c for CaC 6 and YbC 6 to find that the same model reproduces the observed T c in those compounds as well, indicating that it is a unified model for superconductivity in the graphite intercalation compounds with T c ranging over three orders of magnitude. Further enhancement of T c well beyond 10 K is also predicted.

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