Pressure Dependence of Superconductivity in Single-Phase K3C60

Science  28 Jun 1991:
Vol. 252, Issue 5014, pp. 1829-1831
DOI: 10.1126/science.252.5014.1829


The superconducting compound K3C60 (with transition temperature Tc = 19.3 kelvin at ambient pressure), formed as a single phase by reaction of alkali vapor with solids of the icosahedral C60 molecule (buckminsterfullerene), shows a very large decrease of Tc with increasing pressure. Susceptibility measurements on sintered pellets showing bulk superconductivity are reported up to 21 kilobars of pressure, where Tc is already less than 8 kelvin. The results are consistent with a piling up of the density of states at the Fermi level.