Pressure dependence of the superconductivity in PuCoGa₅

We report high-pressure resistivity measurements on a single crystal of PuCoGa₅ using a Bridgman anvil cell with steatite pressure medium. As a function of pressure, the superconducting transition temperature T _c increases from its ambient pressure value of 18.5-22 K at 16.4 GPa. The superconducting transition width increases, suggestive of a high sensitivity to the isotropy of the pressure medium. The stabilisation of the superconductivity over a very large pressure range contrasts unconventional superconducting states in f-electron heavy fermion materials.