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Direct observation of t2g orbital ordering in magnetite

J. Schlappa·C. Schuessler-Langeheine·C. F. Chang·H. Ott·A. Tanaka·Z. Hu·M. W. Haverkort·E. Schierle·E. Weschke·G. Kaindl·L. H. Tjeng
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Abstract

Using soft-x-ray diffraction at the site-specific resonances in the Fe L23 edge, we find clear evidence for orbital and charge ordering in magnetite below the Verwey transition. The spectra show directly that the (001/2) diffraction peak (in cubic notation) is caused by t2g orbital ordering at octahedral Fe2+ sites and the (001) by a spatial modulation of the t2g occupation.

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J. Schlappa, C. Schuessler-Langeheine, C. F. Chang, H. Ott, A. Tanaka, Z. Hu, M. W. Haverkort, E. Schierle, E. Weschke, G. Kaindl, L. H. Tjeng. 2007-11-13. Direct observation of t2g orbital ordering in magnetite. https://doi.org/10.1103/physrevlett.100.026406

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