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Mott transition and suppression of orbital fluctuations in orthorhombic 3$d^{1}$ perovskites

E. Pavarini·S. Biermann·A. Poteryaev·A. I. Lichtenstein·A. Georges·O. K. Andersen
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Abstract

Using $t_{2g}$ Wannier-functions, a low-energy Hamiltonian is derived for orthorhombic $3d^{1}$ transition-metal oxides. Electronic correlations are treated with a new implementation of dynamical mean-field theory for non-cubic systems. Good agreement with photoemission data is obtained. The interplay of correlation effects and cation covalency (GdFeO$_{3}$-type distortions) is found to suppress orbital fluctuations in LaTiO$_{3},$ and even more in YTiO$_{3}$, and to favor the transition to the insulating state.

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E. Pavarini, S. Biermann, A. Poteryaev, A. I. Lichtenstein, A. Georges, O. K. Andersen. 2004-01-19. Mott transition and suppression of orbital fluctuations in orthorhombic 3$d^{1}$ perovskites. https://doi.org/10.1103/physrevlett.92.176403

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