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Abrupt transition in quasiparticle dynamics at optimal doping in a cuprate superconductor system

N. Gedik·J. Orenstein·S. Ono·Yasushi Abe·Yoichi Ando
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Abstract

We report time-resolved measurements of the photoinduced change in reflectivity, Delta R, in the Bi2Sr2Ca(1-y)Dy(y)Cu2O(8+delta) (BSCCO) system of cuprate superconductors as a function of hole concentration. We find that the kinetics of quasiparticle decay and the sign of Delta R both change abruptly where the superconducting transition temperature Tc is maximal. These coincident changes suggest that a sharp transition in quasiparticle dynamics takes place precisely at optimal doping in the BSCCO system.

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N. Gedik, J. Orenstein, S. Ono, Yasushi Abe, Yoichi Ando. 2005-03-15. Abrupt transition in quasiparticle dynamics at optimal doping in a cuprate superconductor system. https://doi.org/10.1103/physrevlett.95.117005

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