Evidence for Strong Electron-Phonon Coupling in Weyl Semimetals*

Since the experimental discovery of topological semimetals (TSM) there has been a flurry of activity focused on identifying signatures of topological transport. However, many of the transport properties display behavior that is dominated by non-topological interactions with the phonon system. A deeper understanding of these TSMs therefore requires investigation of the coupling between the topological electronic system and the non-topological vibrational system. In this presentation we discuss our recent temperature dependent Raman measurements on multiple TSMs which reveal unusual temperature dependence of the linewidths. These linewidths indicate strong electron-phonon coupling in these materials, and furthermore, they show a preponderance of optical phonon decay into electron-hole pairs which seems to be a relatively general feature in TSMs.