Origin of the kink in the band dispersion of the ferromagnetic perovskiteSrRuO3: Electron-phonon coupling

SrRuO${}₃$, a conductive ferromagnetic oxide, is a simple, old, but still fascinating material. Previous angle-resolved photoemission (ARPES) studies found a kink structure in the electron bands, implying unusual electron dynamics. Here, the authors explore the origin of this kink in more detail via ARPES studies of high-quality films of varying thickness. The results indicate that the kink originates from the strong electron-phonon coupling rather than electron-magnon coupling.