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arXiv · 1004.3961

Energy-Dependent Enhancement of the Electron-Coupling Spectrum of the Underdoped Bi2Sr2CaCu2O8+d Superconductor

H. Anzai·A. Ino·T. Kamo·T. Fujita·M. Arita·H. Namatame·M. Taniguchi·A. Fujimori·Z. -X. Shen·M. Ishikado·S. Uchida
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Abstract

We have determined the electron-coupling spectrum of superconducting Bi2Sr2CaCu2O8+d from high-resolution angle-resolved photoemission spectra by two deconvolution-free robust methods. As hole concentration decreases, the coupling spectral weight at low energies ~<15 meV shows a twofold and nearly band-independent enhancement, while that around ~65 meV increases moderately, and that in ~>130 meV decreases leading to a crossover of dominant coupling excitation between them. Our results suggest the competition among multiple screening effects, and provide important clues to the source of sufficiently strong low-energy coupling, {\lambda}LE ~ 1, in underdoped system.

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H. Anzai, A. Ino, T. Kamo, T. Fujita, M. Arita, H. Namatame, M. Taniguchi, A. Fujimori, Z. -X. Shen, M. Ishikado, S. Uchida. 2010-04-22. Energy-Dependent Enhancement of the Electron-Coupling Spectrum of the Underdoped Bi2Sr2CaCu2O8+d Superconductor. https://doi.org/10.1016/j.physc.2011.05.244

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