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arXiv · 1102.2464

Pressure cycle of superconducting Cs0.8Fe2Se2: a transport study

G. Seyfarth·D. Jaccard·P. Pedrazzini·A. Krzton-Maziopa·E. Pomjakushina·K. Conder·Z. Shermadini
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Abstract

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 ρ(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.

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G. Seyfarth, D. Jaccard, P. Pedrazzini, A. Krzton-Maziopa, E. Pomjakushina, K. Conder, Z. Shermadini. 2011-04-12. Pressure cycle of superconducting Cs0.8Fe2Se2: a transport study. https://doi.org/10.1016/j.ssc.2011.03.014

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