Measuring the Electron–Phonon Interaction in Two-Dimensional Superconductors with He-Atom Scattering

Abstract

Helium-atom scattering (HAS) spectroscopy from conducting surfaces has been shown to provide direct information on the electron–phonon interaction, more specifically the mass-enhancement factor λ from the temperature dependence of the Debye–Waller exponent, and the mode-selected electron–phonon coupling constants λQν from the inelastic HAS intensities from individual surface phonons. The recent applications of the method to superconducting ultra-thin films, quasi-1D high-index surfaces, and layered transition-metal and topological pnictogen chalcogenides are briefly reviewed.

Keywords

• electron-phonon interaction
• superconductivity
• topological insulator
• topological materials
• transition metal dichalcogenide
• charge density wave