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arXiv · 1401.4091

Short-Range Correlations in Magnetite above the Verwey Temperature

Alexey Bosak·Dmitry Chernyshov·Moritz Hoesch·Przemyslaw Piekarz·Mathieu Le Tacon·Michael Krisch·Andrzej Kozlowski·Andrzej M. Oleś·Krzysztof Parlinski
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Abstract

Magnetite, Fe$_3$O$_4$, is the first magnetic material discovered and utilized by mankind in Ancient Greece, yet it still attracts attention due to its puzzling properties. This is largely due to the quest for a full and coherent understanding of the Verwey transition that occurs at $T_V=124$ K and is associated with a drop of electric conductivity and a complex structural phase transition. A recent detailed analysis of the structure, based on single crystal diffraction, suggests that the electron localization pattern contains linear three-Fe-site units, the so-called trimerons. Here we show that whatever the electron localization pattern is, it partially survives up to room temperature as short-range correlations in the high-temperature cubic phase, easily discernible by diffuse scattering. Additionally, {\it ab initio} electronic structure calculations reveal that characteristic features in these diffuse scattering patterns can be correlated with the Fermi surface topology.

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Alexey Bosak, Dmitry Chernyshov, Moritz Hoesch, Przemyslaw Piekarz, Mathieu Le Tacon, Michael Krisch, Andrzej Kozlowski, Andrzej M. Oleś, Krzysztof Parlinski. 2014-01-16. Short-Range Correlations in Magnetite above the Verwey Temperature. https://doi.org/10.1103/physrevx.4.011040

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