The optical properties of V 2 O 3 thin films are investigated across the insulator-to-metal transition and in the metallic state. The spectral weight transfer observed across the transition, over an energy scale of 5 eV, is consistent with the Mott-Hubbard model for correlated electron systems. In the metallic phase, a strong Drude peak is observed, which exhibits a pronounced temperature dependence related to the transfer of states from the Hubbard bands to the quasiparticle peaks as the temperature is reduced. The analysis of the far-infrared spectra reveals signatures of strong electronic correlations in V 2 O 3. Finally, a comparison to VO 2 data is presented.

An optical study of the effects of strain and heterostructuring on nickelates is presented. The optical conductivity data obtained for a series of ultrathin films of NdNiO 3 with varying amounts of strain reveal that two mechanisms, each associated with a different energy scale, are responsible for the tuning of the Drude-like spectral weight as a function of strain. Additionally, the optical properties of the LaNiO 3 layers in a LaNiO 3 /LaAlO 3 superlattice are investigated, showing that the coherent Drude transport associated with strained LaNiO 3 is suppressed due to the presence of the LaAlO 3 interlayers.