Possible absence of trimeron correlations above the Verwey temperature in Fe&lt;sub&gt;3&lt;/sub&gt;O&lt;sub&gt;4&lt;/sub&gt;

Elnaggar, H.; Wang, R.; Lafuerza, S.; Paris, E.; Komarek, A.C.; Guo, H.; Tseng, Y.; McNally, D.; Frati, F.; Haverkort, M.W.; Sikora, M.; Schmitt, T.; de Groot, F.M.F.

doi:10.1103/PhysRevB.101.085107

Possible absence of trimeron correlations above the Verwey temperature in Fe₃O₄

Elnaggar H, Wang R, Lafuerza S, Paris E, Komarek AC, Guo H, Tseng Y, McNally D, Frati F, Haverkort MW, Sikora M, Schmitt T & de Groot FMF

Citation

Elnaggar, H., Wang, R., Lafuerza, S., Paris, E., Komarek, A. C., Guo, H., … de Groot, F. M. F. (2020). Possible absence of trimeron correlations above the Verwey temperature in Fe₃O₄. Physical Review B, 101(8), 085107 (5 pp.). https://doi.org/10.1103/PhysRevB.101.085107

Persistent URL https://www.dora.lib4ri.ch/psi/islandora/object/psi:29379

The origin of the metal to insulator transition in Fe₃O₄ remains a challenge due to the complexity of the system: it is a mixed valent, strongly correlated system where many interactions such as Jahn-Teller distortion, exchange, and phonons are very close in energetics. A recent interpretation of the Verwey transition as an ordering of a three-site magnetic polaron, the trimeron, has been put forward. Here we investigate the existence of the trimeron correlations in the high-temperature phase of Fe₃O₄ using high-resolution iron 2p3d resonant inelastic scattering magnetic linear dichroism. Guided by theoretical simulations, we reveal that the polarization dependence of the low-energy spin-orbital excitations is incompatible with tetragonal Jahn-Teller trimeron-type distortion. We conclude that the lowest-energy state of the high-temperature phase of Fe₃O₄ arises from an intricate interplay between trigonal crystal-field, exchange, and spin-orbit interactions.