Pressure cycle of superconducting Cs0.8Fe2Se2: a transport study
  We report measurements of the temperature and pressure dependence of the electrical resistivity of single crystalline iron-based chalcogenide Cs0.8Fe2Se2. In this material superconductivity Tc~30K develops from a normal state with extremely large resistivity. At ambient pressure a large "hump" in the resistivity is observed around 200K. Under pressure, the resistivity decreases by two orders of magnitude, concomitant with a sudden Tc suppression around p~8GPa. Even at 9GPa a metallic resistivity state is not recovered, and the {\rho}(T) "hump" is still detected. A comparison of the data measured upon increasing and decreasing the external pressure leads us to suggest that superconductivity is not related to this hump. 
G. Seyfarth (DPMC), D. Jaccard (DPMC), P. Pedrazzini (CNEA), A.   Krzton-Maziopa (PSI1), E. Pomjakushina (PSI1), K. Conder (...
cond-mat.supr-con