Electron-phonon coupling in the spin-split valence band of single layer WS${}_2$

Abstract

The absence of inversion symmetry leads to a strong spin-orbit splitting of the upper valence band of semiconducting single layer transition metal dichalchogenides such as MoS${}_2$ or WS${}_2$. This permits a direct comparison of the electron-phonon coupling strength in states that only differ by their spin. Here, the electron-phonon coupling in the valence band maximum of single-layer WS${}_2$ is studied by first principles calculations and angle-resolved photoemission. The coupling strength is found to be drastically different for the two spin-split branches, with calculated values of ${\lambda }_K=$0.0021 and 0.40 for the upper and lower spin-split valence band of the free-standing layer, respectively. This difference is somewhat reduced when including scattering processes involving the Au(111) substrate present in the experiment and the experimental results confirm the strongly branch-dependent coupling strength.

5 pages, 4 figures

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Cited by in corpus (3)

• Electron-phonon interaction and transport properties of metallic bulk and monolayer transition metal dichalcogenide TaS${}_2$
• Epitaxial single layer NbS${}_2$ on Au(111): synthesis, structure, and electronic properties
• Spectral functions of CVD grown MoS${}_2$ monolayers after chemical transfer onto Au surface