Doping dependence of the electron-phonon and electron-spin fluctuation interactions in the high-$T_{c}$ superconductor Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$

Elbert E. M. Chia; D. Springer; Saritha K. Nair; X. Q. Zou; S. A. Cheong; C. Panagopoulos; T. Tamegai; H. Eisaki; S. Ishida; S. Uchida; A. J. Taylor; Jian-Xin Zhu

arXiv · 1107.1924

Doping dependence of the electron-phonon and electron-spin fluctuation interactions in the high-$T_{c}$ superconductor Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$

Elbert E. M. Chia·D. Springer·Saritha K. Nair·X. Q. Zou·S. A. Cheong·C. Panagopoulos·T. Tamegai·H. Eisaki·S. Ishida·S. Uchida·A. J. Taylor·Jian-Xin Zhu

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Abstract

Using ultrafast optical techniques, we detect two types of bosons strongly coupled to electrons in the family of Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$ from the underdoped to overdoped regimes. The different doping dependences of the electron-boson coupling strengths enables us to identify them as phonons and spin fluctuations: electron-phonon coupling ($\lambda_{e-ph}$) peaks at optimal doping, and electron-spin fluctuation coupling ($\lambda_{e-sf}$) decreases monotonically with doping. This observation is consistent with two facts: (1) superconductivity is in close proximity with antiferromagnetism at low dopings, and (2) a pronounced lattice renormalization effect at larger dopings.

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Elbert E. M. Chia, D. Springer, Saritha K. Nair, X. Q. Zou, S. A. Cheong, C. Panagopoulos, T. Tamegai, H. Eisaki, S. Ishida, S. Uchida, A. J. Taylor, Jian-Xin Zhu. 2011-07-11. Doping dependence of the electron-phonon and electron-spin fluctuation interactions in the high-$T_{c}$ superconductor Bi$_{2}$Sr$_{2}$CaCu$_{2}$O$_{8+\delta}$. https://arxiv.org/abs/1107.1924

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