Tunable electron scattering mechanism in plasmonic SrMoO₃ thin films

4d transition metal perovskite oxides serve as suitable testbeds for the study of strongly correlated metallic properties. Among these, SrMoO₃ (SMO) exhibits remarkable electrical conductivity at room temperature. The temperature-dependent resistivity (ρ(T)) exhibits a Fermi-liquid behavior below the transition temperature T^∗, reflecting the dominant electron-electron interaction. Above T^∗, electron-phonon interaction becomes more appreciable. In this study, we employed the power-law scaling of ρ(T) to rigorously determine the T^∗. We further demonstrate that the T^∗ can be modified substantially by ∼40 K in epitaxial thin films. It turns out that the structural quality determines T^∗. Whereas the plasma frequency could be tuned by the change in the electron-electron interaction via the effective mass enhancement, we show that the plasmonic properties are more directly governed by the electron-impurity scattering. The facile control of the electron scattering mechanism through structural quality modulation can be useful for plasmonic sensing applications in the visible region.