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Theory of Insulator Metal Transition and Colossal Magnetoresistance in Doped Manganites

T. V. Ramakrishnan·H. R. Krishnamurthy·S. R. Hassan·G. V. Pai
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Abstract

The persistent proximity of insulating and metallic phases, a puzzling characterestic of manganites, is argued to arise from the self organization of the twofold degenerate e_g orbitals of Mn into localized Jahn-Teller(JT) polaronic levels and broad band states due to the large electron - JT phonon coupling present in them. We describe a new two band model with strong correlations and a dynamical mean-field theory calculation of equilibrium and transport properties. These explain the insulator metal transition and colossal magnetoresistance quantitatively, as well as other consequences of two state coexistence.

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T. V. Ramakrishnan, H. R. Krishnamurthy, S. R. Hassan, G. V. Pai. 2003-08-19. Theory of Insulator Metal Transition and Colossal Magnetoresistance in Doped Manganites. https://doi.org/10.1103/physrevlett.92.157203

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