METALLIC CSI AT PRESSURES OF UP TO 220 GIGAPASCALS

Direct electrical transport measurements in a diamond anvil cell provi de evidence for the metallization of cesium iodide (Csl) at a pressure of 115 gigapascals, A drop in the temperature dependence of the resis tance was found at pressures above 180 gigapascals, indicating that th e Csl was superconductive. The superconductivity changed under the inf luence of a magnetic field to a Lower critical temperature ana disappe ared above 0.3 tesla. The highest critical temperature at which superc onductivity was observed was 2 kelvin, and the critical temperature de creased with increasing pressure.