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arXiv · 0808.1174

Orbital ordering in undoped manganites via a generalized Peierls instability

S. Yarlagadda·P. B. Littlewood·M. Mitra·R. K. Monu
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Abstract

We study the ground state orbital ordering of $LaMnO_3$, at weak electron-phonon coupling, when the spin state is A-type antiferromagnet. We determine the orbital ordering by extending to our Jahn-Teller system a recently developed Peierls instability framework for the Holstein model [1]. By using two-dimensional dynamic response functions corresponding to a mixed Jahn-Teller mode, we establish that the $Q_2$ mode determines the orbital order.

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S. Yarlagadda, P. B. Littlewood, M. Mitra, R. K. Monu. 2009-11-23. Orbital ordering in undoped manganites via a generalized Peierls instability. https://doi.org/10.1103/physrevb.80.235123

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