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The Anti-Jahn-Teller Polaron in LaMnO$_3$

Philip B. Allen·Vasili Perebeinos
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Abstract

Distortions of the oxygen sublattice couple to $e_g$ orbitals of Mn$^{3+}$ and drive a cooperative Jahn-Teller (orbital ordering) transition in LaMnO$_3$. A simple model for this transition is studied. Without further adjustment, the model predicts the shape and stability of small (anti-Jahn-Teller) polarons which form when holes are doped into the material. This leads to a new description of the lightly doped insulator, the anti-ferromagnetic to ferromagnetic transition, and the metal-insulator transition.

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Philip B. Allen, Vasili Perebeinos. 1999-06-08. The Anti-Jahn-Teller Polaron in LaMnO$_3$. https://doi.org/10.1103/physrevb.60.10747

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