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Mechanism of the Verwey transition in magnetite

P. Piekarz·K. Parlinski·A. M. Oles
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Abstract

By combining {\it ab initio} results for the electronic structure and phonon spectrum with the group theory, we establish the origin of the Verwey transition in Fe$_3$O$_4$. Two primary order parameters with $X_3$ and $Δ_5$ symmetries are identified. They induce the phase transformation from the high-temperature cubic to the low-temperature monoclinic structure. The on-site Coulomb interaction $U$ between 3d electrons at Fe ions plays a crucial role in this transition -- it amplifies the coupling of phonons to conduction electrons and thus opens a gap at the Fermi energy. {\it Published in Phys. Rev. Lett. {\bf 97}, 156402 (2006).}

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P. Piekarz, K. Parlinski, A. M. Oles. 2006-10-13. Mechanism of the Verwey transition in magnetite. https://doi.org/10.1103/physrevlett.97.156402

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