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arXiv · 1103.4804

Buckling induced Zener polaron instability in half-doped manganites

Paolo Barone·Silvia Picozzi·Jeroen van den Brink
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Abstract

By calculating the electronic, orbital, magnetic and lattice structure of half-doped manganites we establish the central role of oxygen buckling caused by the tilting of the MnO$_6$ octahedra -- in essence a steric effect. The buckling itself does not change the Mn-Mn bonds. Instead it drives the system towards an instability where these bonds can dimerize. In presence of electron-electron interactions, this instability can fully develop and beyond a critical buckling a Zener polaron groundstate with dimerized spins, lattice and orbitals forms spontaneously, resulting in a multiferroic state.

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Paolo Barone, Silvia Picozzi, Jeroen van den Brink. 2011-09-25. Buckling induced Zener polaron instability in half-doped manganites. https://doi.org/10.1103/physrevb.83.233103

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