Band anisotropy and effective mass renormalization in strained metallic VO₂ (101) thin films

We explore how strain impacts the band structure of metallic-phase VO₂ thin films deposited on TiO₂(101) substrates. Employing a combination of X-ray absorption linear dichroism and valence band measurements, we demonstrate that strain can alter the intrinsic band structure anisotropy of metallic VO₂. Our findings reveal that reducing the thickness of VO₂ films leads to a more isotropic band structure. This observation is further supported by an analysis of the electronic population redistribution in the \({d}_{{||}}{-}{\pi }^{* }\) $d_{\mathit{||}}\mathit{-}{\pi }^{*}$ bands, which affects the screening length and induces effective mass renormalization. Overall, our results underscore the potential of strain manipulation in tailoring the electronic structure uniformity of thin films, thereby expanding the scope for engineering VO₂ functionalities.