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Ferromagnetic, A-type, and Charge-Ordered CE-type States in Doped Manganites using Jahn-Teller Phonons

Seiji Yunoki·Takashi Hotta·Elbio Dagotto
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Abstract

The two-orbital model for manganites with both non-cooperative and cooperative Jahn-Teller phonons is studied at hole density x=0.5 using Monte Carlo techniques. The phase diagram is obtained varying the electron-phonon coupling and the $\rm t_{2g}$-spins exchange. The insulating CE-type charge- and orbital-ordered state with the $z$-axis charge $stacking$ observed in narrow-bandwidth manganites is stabilized in the simulations. Its charge gap $Δ_{\rm CO}$ is much larger than the critical temperature $\rm k_B T_{CO}$. Metallic-like A-type and ferromagnetic states are also obtained in the same framework, and the phase boundaries among them have first-order characteristics.

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Seiji Yunoki, Takashi Hotta, Elbio Dagotto. 1999-09-16. Ferromagnetic, A-type, and Charge-Ordered CE-type States in Doped Manganites using Jahn-Teller Phonons. https://doi.org/10.1103/physrevlett.84.3714

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