Molecular solids whose cooperative electronic properties are based purely on π-electrons from carbon atoms offer a fertile ground in the search for exotic states of matter, including unconventional superconductivity. C₆₀-based solids with stoichiometry A₃C₆₀ (A = alkali metal) are archetypal examples of molecular superconductors with the highest superconducting transition temperatures (T_c = 38 K) among all molecular systems known [1]. More recently, we have shown that they also display the highest upper critical magnetic field (H_c2 > 90 Tesla) among all known three-dimensional superconducting solids [2]. The dominance of strong electron correlations in defining their behavior poses significant challenges for understanding the highly robust superconducting response to both temperature and magnetic field in these highly correlated organic metals. Here I will briefly describe this field of fullerene science with emphasis on its current status and future prospects.

References

[1] R. H. Zadik et al., Science Advances 1, e1500059 (2015).

[2] Y. Kasahara et al., Nature Communications, in press.