Observation of the pseudogap features in overdoped Bi2Sr2CaCu2O8+d by breakjunction tunneling spectroscopy

ORAL

Abstract

Tunneling measurements of Bi2Sr2CaCu2O8+d single crystals with different oxygen doping have been carried out by using break-junction technique to study the pseudogap in the overdoped regime. The normal-state pseudogap has been observed clearly in the three overdoped crystals with Tc = 90 K, 82 K, and 72 K, respectively. Furthermore, direct measurements on the pseudogap opening temperature T*, by tracing the disappearance of the tunneling conductance peak, reveal that the relationship of T* versus hole concentration is linear and its extrapolation just crosses the end of the superconducting phase boundary.

*This work was Supported by a grant for State Key Program for Basic Research of China, and the National Center for Research and Development on Superconductivity.

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Authors

  • Y. Xuan

  • H. J. Tao

  • Z. Z. Li

  • B. R. Zhao

  • Z. X. Zhao

    • National Laboratory for Superconductivity, Institute of Physics and Center for Condensed Mater Physics, Chinese Academy of Sciences, China

  • C.T. Lin

    • Max-Planck-Institut f\"{u}r Festk\"{o}rperforschung, 70569 Stuttgart, Germany