DFT + DMFT calculations for epitaxially strained LaTiO3

Even though bulk LaTiO3 is a Mott insulator, metallic properties have been reported for thin films of LaTiO3 grown on SrTiO3. Such metallicity, can be due to a number of factors such as: electronic reconstruction at the interface, defects, or substrate-induced structural deformations. In order to identify the origin of the observed metallicity, we perform density functional theory plus dynamical mean field theory (DFT+DMFT) calculations for epitaxially strained LaTiO3. First, we use standard DFT to accurately relax the structure under the epitaxial constraint, and we monitor hopping amplitudes and crystal-field splitting as a function of strain. Then, we calculate the electronic properties for the strained structures using DMFT. Based on our results we address the question whether the strain-induced structural modifications of LaTiO3 are enough to change this insulator into a metal.