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arXiv · 0902.1636

Electron-Phonon Coupling in High-Temperature Cuprate Superconductors Determined from Electron Relaxation Rates

C. Gadermaier·A. S. Alexandrov·V. V. Kabanov·P. Kusar·T. Mertelj·X. Yao·C. Manzoni·D. Brida·G. Cerullo·D. Mihailovic
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Abstract

We determined electronic relaxation times via pump-probe optical spectroscopy using sub-15 fs pulses for the normal state of two different cuprate superconductors.We show that the primary relaxation process is the electron-phonon interaction and extract a measure of its strength, the second moment of the Eliashberg functionλ<ω^{2}>=800\pm200 meV^{2} for La_{1.85}Sr_{0.15}CuO_{4} and λ<ω^{2}>=400\pm100 meV^{2} for YBa_{2}Cu_{3}O_{6.5}. These values suggest a possible fundamental role of the electron-phonon interaction in the superconducting pairing mechanism.

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C. Gadermaier, A. S. Alexandrov, V. V. Kabanov, P. Kusar, T. Mertelj, X. Yao, C. Manzoni, D. Brida, G. Cerullo, D. Mihailovic. 2010-12-15. Electron-Phonon Coupling in High-Temperature Cuprate Superconductors Determined from Electron Relaxation Rates. https://doi.org/10.1103/physrevlett.105.257001

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