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Manganites at Quarter Filling: Role of Jahn-Teller Interactions

Jan Bała·Peter Horsch·Frank Mack
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Abstract

We have analyzed different correlation functions in a realistic spin-orbital model for half-doped manganites. Using a finite-temperature diagonalization technique the CE phase was found in the charge-ordered phase in the case of small antiferromagnetic interactions between $t_{2g}$ electrons. It is shown that a key ingredient responsible for stabilization of the CE-type spin and orbital-ordered state is the cooperative Jahn-Teller (JT) interaction between next-nearest Mn$^{+3}$ neighbors mediated by the breathing mode distortion of Mn$^{+4}$ octahedra and displacements of Mn$^{+4}$ ions. The topological phase factor in the Mn-Mn hopping leading to gap formation in one-dimensional models for the CE phase as well as the nearest neighbor JT coupling are not able to produce the zigzag chains typical for the CE phase in our model.

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Jan Bała, Peter Horsch, Frank Mack. 2004-01-14. Manganites at Quarter Filling: Role of Jahn-Teller Interactions. https://doi.org/10.1103/physrevb.69.094415

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