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Insulator-Metal transition in the Doped 3d1 Transition Metal Oxide LaTiO3

L. Craco·M. S. Laad·S. Leoni·E. Müller-Hartmann
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Abstract

The doping induced insulator-metal transition in $La_{1-x}Sr_{x}TiO_{3}$ is studied using the ab-initio LDA+DMFT method. Combining the LDA bandstructure for the actual, distorted structure found recently with multi-orbital DMFT to treat electronic correlations, we find: $(i)$ ferro-orbital order in the Mott insulating state without orbital degeneracy, $(ii)$ a continuous filling induced transition to the paramagnetic metal (PM) with $x$, and $(iii)$ excellent quantitative agreement with published photoemission data for the case of 6% doping. Our results imply that this system can be described as a Mott-Hubbard system without orbital (liquid) degeneracy.

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L. Craco, M. S. Laad, S. Leoni, E. Müller-Hartmann. 2003-09-16. Insulator-Metal transition in the Doped 3d1 Transition Metal Oxide LaTiO3. https://arxiv.org/abs/cond-mat/0309370

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