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arXiv · 1910.09859

Ultrafast Quasiparticle Dynamics and Electron-Phonon Coupling in (Li0.84Fe0.16)OHFe0.98Se

Q. Wu·H. X. Zhou·Y. L. Wu·L. L. Hu·S. L. Ni·Y. C. Tian·F. Sun·F. Zhou·X. L. Dong·Z. X. Zhao·Jimin Zhao
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Abstract

Distinctive superconducting behaviors between bulk and monolayer FeSe make it challenging to obtain a unified picture of all FeSe-based superconductors. We investigate the ultrafast quasiparticle (QP) dynamics of an intercalated superconductor (Li1-xFex)OHFe1-ySe, which is a bulk crystal but shares a similar electronic structure with single-layer FeSe on SrTiO3. We obtain the electron-phonon coupling (EPC) constant {\lambda}A1g (0.22 +/- 0.04), which well bridges that of bulk FeSe crystal and single-layer FeSe on SrTiO3. Moreover, we find that such a positive correlation between {\lambda}A1g and superconducting Tc holds among all known FeSe-based superconductors, even in line with reported FeAs-based superconductors. Our observation indicates possible universal role of EPC in the superconductivity of all known categories of iron-based superconductors, which is a critical step towards achieving a unified superconducting mechanism for all iron-based superconductors.

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Q. Wu, H. X. Zhou, Y. L. Wu, L. L. Hu, S. L. Ni, Y. C. Tian, F. Sun, F. Zhou, X. L. Dong, Z. X. Zhao, Jimin Zhao. 2019-10-22. Ultrafast Quasiparticle Dynamics and Electron-Phonon Coupling in (Li0.84Fe0.16)OHFe0.98Se. https://doi.org/10.1088/0256-307x%2F37%2F9%2F097802

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