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arXiv · 1305.6194

Doping Evolution of Nodal Band Renormalization in Bi2Sr2CuO6+d Superconductor Revealed by Laser-Based Angle-Resolved Photoemission Spectroscopy

Abstract

High resolution laser-based angle-resolved photoemission measurements have been carried out on Bi2Sr2CuO6+d superconductor covering a wide doping range from heavily underdoped to heavily overdoped samples. Two obvious energy scales are identified in the nodal dispersions: one is the well-known 50-80 meV high energy kink and the other is <10 meV low energy kink. The high energy kink increases monotonously in its energy scale with increasing doping and shows weak temperature dependence, while the low energy kink exhibits a non-monotonic doping dependence with its coupling strength enhanced sharply below Tc. These systematic investigations on the doping and temperature dependence of these two energy scales favor electron-phonon interactions as their origin. They point to the importance in involving the electron-phonon coupling in understanding the physical properties and the superconductivity mechanism of high temperature cuprate superconductors.

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Yingying Peng, Jianqiao Meng, Lin Zhao, Yan Liu, Junfeng He, Guodong Liu, Xiaoli Dong, Shaolong He, Jun Zhang, Chuangtian Chen, Zuyan Xu, X. J. Zhou. 2013-05-27. Doping Evolution of Nodal Band Renormalization in Bi2Sr2CuO6+d Superconductor Revealed by Laser-Based Angle-Resolved Photoemission Spectroscopy. https://doi.org/10.1088/0256-307x%2F30%2F6%2F067402

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