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Orbital correlations in monolayer manganites - From spin t-J model to orbital t-J model

M. Daghofer·A. M. Oles
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Abstract

On the example of monolayer manganites we show that the theoretical ideas developed long ago along the derivation of the spin t-J model from the Hubbard model are nowadays very helpful in strongly correlated oxides with partly filled degenerate orbitals. We analyze a realistic orbital t-J model for e_g electrons in La_{1-x}Sr_{1+x}MnO_4 monolayer manganites, and discuss the evolution of spin and orbital correlations under increasing doping by performing exact diagonalization of finite clusters, with electronic kinetic energy determined self-consistently at finite temperature by classical Monte Carlo for t_2g spins. Several experimental results are reproduced.

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M. Daghofer, A. M. Oles. 2007-03-05. Orbital correlations in monolayer manganites - From spin t-J model to orbital t-J model. https://arxiv.org/abs/cond-mat/0703127

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