Unconventional Superconductivity in Na X Coo 2 · Yh 2 O
نویسندگان
چکیده
We synthesized powder samples of NaxCoO2 · yH2O changing the volume of the water in the hydration process, then investigated their superconducting properties,. It was proved that the volume of water is one of key parameters to obtain a single phase of NaxCoO2 · yH2O with good superconducting properties. The transition temperature, Tc, of the sample changed gradually while it was stored in the atmosphere of 70% humidity. Superconducting behavior under high magnetic field was very sensitive to Tc. Hc2 of a high quality sample with high Tc seemed very high.
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تاریخ انتشار 2004