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Metal-Insulator Transition in Mn Perovskite Compounds

Yukitoshi Motome·Hiroki Nakano·Masatoshi Imada
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Abstract

We discuss Mott insulating and metallic phases of a model with $e_g$ orbital degeneracy to understand physics of Mn perovskite compounds. Quantum Monte Carlo and Lanczos diagonalization results are discussed in this model. To reproduce experimental results on charge gap and Jahn-Teller distortions, we show that a synergy between the strong correlation effects and the Jahn-Teller coupling is important. The incoherent charge dynamics and strong charge fluctuations are characteristic of the metallic phase accompanied with critical enhancement of short-ranged orbital correlation near the insulator.

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Yukitoshi Motome, Hiroki Nakano, Masatoshi Imada. 1998-11-16. Metal-Insulator Transition in Mn Perovskite Compounds. https://arxiv.org/abs/cond-mat/9811221

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