Role of bosonic modes in the mechanism of high temperature Bi₂Sr₂CaCu₂O_8+δ superconductors using ultrafast optical techniques

2008/06/16 by Zhu, Jian-Xin, Chia, Elbert E. M., Tamegai, T. +4
#FOS: Physical sciences #Strongly Correlated Electrons (cond-mat.str-el) #Superconductivity (cond-mat.supr-con)

paper · doi:10.48550/arxiv.0806.2664

Abstract

Using ultrafast optical techniques, we probe the hole-doping dependence of the electron-boson coupling constant λ in Bi₂Sr₂CaCu₂O_8+δ. In the overdoped region, we observe a correlation between (λ) and the superconducting transition temperature T_c. Upon performing the McMillan analysis, however, we find that λ is too small to explain the high T_c's, and that the Coulomb pseudopotential μ^∗ is negative. Our analysis therefore reveals two components in the mechanism of high-T_c superconductivity -- a dominant pre-existing pairing interaction, together with a weaker electron-phonon interaction that fine-tunes T_c.

Related

• Doping dependence of the electron-phonon and electron-spin fluctuation interactions in the high-T_c superconductor Bi₂Sr₂CaCu₂O_8+δ
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• Impact of Optical Modes on the Pairing Potential in Bilayer Cuprates
• Light-induced Asymmetric Pseudogap below T_c in cuprates
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