Superconductivity at 155 K
نویسندگان
چکیده
Transition to a superconducting zero-resistance state at 155 K is observed for the first time in bulk material. A new five-element compound has been synthesized with nominal composition YIBa2Cu3F20y. Fluorine plays a critical role in achieving this eAect. X-ray diffraction and electron microprobe analysis indicate that the samples are multiphasic. Evidence is presented that the samples contain superconducting phases with onset temperatures considerably above 155 K. Magnetic measurements suggest a fluxtrapping eftect below 260 K, and diamagnetic deviations from Curie-Weiss behavior in the range 250 K ~ T ~ 100 K indicate a Meissner efect in a small superconducting volume fraction.
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