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Metallizing the Mott insulator TiOCl by electron doping: a view from LDA+DMFT

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

Based on recent experiments, we describe the Mott insulating, but undimerized state of $TiOCl$ using the local-density approximation combined with multi-orbital dynamical mean field theory (LDA+DMFT) for this $3d^{1}$ system.Good agreement with the high estimated value of the superexchange is obtained. The possibility of an electron-doped insulator-metal transition in $TiOCl$ is investigated in this scheme and a Mott-Hubbard transition with a jump in carrier density {\it inside} the metallic state is found. Clear, co-incident, discontinuous changes in orbital occupations are observed, showing that such a transition would involve strong, multi-orbital correlations. These results call for studies on suitably intercalated $TiOCl$ that may induce metallization and, possibly, unconventional superconductivity.

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L. Craco, M. S. Laad, E. Müller-Hartmann. 2004-10-19. Metallizing the Mott insulator TiOCl by electron doping: a view from LDA+DMFT. https://arxiv.org/abs/cond-mat/0410472

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