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arXiv · 1407.6774

Raman scattering investigation of the electron-phonon coupling in superconducting Nd(O,F)BiS$_2$

S. F. Wu·P. Richard·X. B. Wang·C. S. Lian·S. M. Nie·J. T. Wang·N. L. Wang·H. Ding
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Abstract

We have performed polarized Raman scattering measurements on the newly discovered superconductor Nd(O,F)BiS$_2$ ($T_c = 4$ K). We observe 2 Raman active modes, with frequencies in accordance with first-principles calculations. One A$_{1g}$ phonon mode at 112.4 cm$^{-1}$ exhibits a Fano line shape due to electron-phonon coupling. We find a resonance for this mode at 2.45 eV excitation energy. We estimate a 0.68 contribution of this mode to the electron-phonon coupling constant $\lambda$. Our Raman results suggest that the BiS$_2$-based superconductors are possibly phonon-mediated BCS superconductors.

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S. F. Wu, P. Richard, X. B. Wang, C. S. Lian, S. M. Nie, J. T. Wang, N. L. Wang, H. Ding. 2014-07-25. Raman scattering investigation of the electron-phonon coupling in superconducting Nd(O,F)BiS$_2$. https://doi.org/10.1103/physrevb.90.054519

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