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arXiv · 0905.0511

Electron-phonon superconductivity in non-centrosymmetric LaNiC$_2$: first principles calculations

A. Subedi·D. J. Singh
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Abstract

We report first principles calculations of the electronic structure and electron-phonon coupling in the non-centrosymmetric superconductor LaNiC$_2$. These show that the material is a conventional electron-phonon superconductor with intermediate coupling. There are large contributions to the coupling by two low frequency C non-bond-stretching modes, one of which has strong Kohn anomalies. Since LaNiC$_2$ lacks inversion symmetry, the pairing is of dominant s-wave type with some mixture of p-wave character. This will give exponential decay in the specific heat.

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A. Subedi, D. J. Singh. 2009-05-05. Electron-phonon superconductivity in non-centrosymmetric LaNiC$_2$: first principles calculations. https://doi.org/10.1103/physrevb.80.092506

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