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

• 来源期刊: 中国物理快报（英文版）
• 年，卷（期）: 2013,（6）
• 页码范围: 194-197
• 页数: 4页
• 语种: 英文
• DOI: 10.1088/0256-307X/30/6/067402

摘要

High resolution laser-based angle-resolved photoemission measurements are carried out on Bi2Sr2 CuO6+δ 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 50-80meV high energy kink and the other is <l0meV 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 Te . 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.