Article

Mott transition and suppression of orbital fluctuations in orthorhombic 3d(1) perovskites

INFM and Dipartimento di Fisica A. Volta, Università di Pavia, Via Bassi 6, I-27100 Pavia, Italy.
Physical Review Letters (Impact Factor: 7.73). 05/2004; 92(17):176403. DOI: 10.1103/PhysRevLett.92.176403
Source: PubMed

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 noncubic systems. Good agreement with photoemission data is obtained. The interplay of correlation effects and cation covalency (GdFeO3-type distortions) is found to suppress orbital fluctuations in LaTiO3 and even more in YTiO3, and to favor the transition to the insulating state.

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