Strain Engineering the Quasiparticle Band Structure of SrVO₃ Thin Films

The perovskite SrVO₃ is a correlated metal that possesses a simple 3d¹ electronic configuration and thus has served as a model system for studying electron correlation effects. Using angle-resolved photoemission spectroscopy, we investigated how the electronic structure of SrVO₃ thin films evolves as a function of epitaxial strain on SrTiO₃, LSAT, and NdGaO₃ substrates. We find that increasing biaxial strain not only drives a redshift in the t_2g coherent quasiparticle band, but surprisingly, also the high-energy incoherent spectral weight at ~ 1.5 eV. We explore the origins of the dispersive incoherent feature, which was commonly associated either with oxygen vacancies or a Hubbard-like feature, but has more recently been considered a plasmonic replica band. Tuning strain helps better our understanding of this satellite feature and more broadly for the application of SrVO₃ as a highly conductive transparent oxide.