Inelastic x-ray scattering and ab initio calculation are applied to investigate the lattice dynamics and electron-phonon coupling of the ternary silicide superconductor CaAlSi (P 6̄ m2). A soft c -axis polarized mode is clearly observed along the Γ-A-L symmetry directions. The soft mode is strongly anharmonically broadened at room temperature, but at 10 K, its linewidth narrows and comes in good agreement with calculations of linear electron-phonon coupling. This establishes a coherent description of the detailed phonon properties into this system and links them clearly and consistently with the superconductivity.
|Journal||Physical Review B - Condensed Matter and Materials Physics|
|Publication status||Published - Apr 7 2008|
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics