Infrared Probe of Transition from Superconductor to Nonmetal in YBa2sCu12xZnxd4O8
نویسندگان
چکیده
We report on a study of the optical conductivity of single crystals of the high-Tc superconductor YBa2Cu4O8 in which superconductivity is suppressed by random substitution of Cu with Zn. The a-axis infrared spectrum, which is a direct measure of the charge dynamics in the CuO2 planes, is dominated by a bound state at ø120 cm21. This indicates that the low-energy electronic states are on the verge of localization driven by the Zn impurities. [S0031-9007(98)07061-6]
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