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Orbital polarons and ferromagnetic insulators in manganites

T. Mizokawa·D. I. Khomskii·G. A. Sawatzky
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Abstract

We argue that in lightly hole doped perovskite-type Mn oxides the holes (Mn$^{4+}$ sites) are surrounded by nearest neighbor Mn$^{3+}$ sites in which the occupied $3d$ orbitals have their lobes directed towards the central hole (Mn$^{4+}$) site and with spins coupled ferromagnetically to the central spin. This composite object, which can be viewed as a combined orbital-spin-lattice polaron, is accompanied by the breathing type (Mn$^{4+}$) and Jahn-Teller type (Mn$^{3+}$) local lattice distortions. We present calculations which indicate that for certain doping levels these orbital polarons may crystallize into a charge and orbitally ordered ferromagnetic insulating state.

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T. Mizokawa, D. I. Khomskii, G. A. Sawatzky. 2000-11-04. Orbital polarons and ferromagnetic insulators in manganites. https://doi.org/10.1103/physrevb.63.024403

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