Ferromagnetic coupling of mononuclear Fe centers in a self-assembled metal-organic network on Au(111)

T. R. Umbach; M. Bernien; C. F. Hermanns; A. Krüger; V. Sessi; I. Fernandez-Torrente; P. Stoll; J. I. Pascual; K. J. Franke; W. Kuch

doi:10.1103/physrevlett.109.267207

arXiv · 1212.3434

Ferromagnetic coupling of mononuclear Fe centers in a self-assembled metal-organic network on Au(111)

T. R. Umbach·M. Bernien·C. F. Hermanns·A. Krüger·V. Sessi·I. Fernandez-Torrente·P. Stoll·J. I. Pascual·K. J. Franke·W. Kuch

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Abstract

The magnetic state and magnetic coupling of individual atoms in nanoscale structures relies on a delicate balance between different interactions with the atomic-scale surrounding. Using scanning tunneling microscopy, we resolve the self-assembled formation of highly ordered bilayer structures of Fe atoms and organic linker molecules (T4PT) when deposited on a Au(111) surface. The Fe atoms are encaged in a three-dimensional coordination motif by three T4PT molecules in the surface plane and an additional T4PT unit on top. Within this crystal field, the Fe atoms retain a magnetic ground state with easy-axis anisotropy, as evidenced by X-ray absorption spectroscopy and X-ray magnetic circular dichroism. The magnetization curves reveal the existence of ferromagnetic coupling between the Fe centers.

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T. R. Umbach, M. Bernien, C. F. Hermanns, A. Krüger, V. Sessi, I. Fernandez-Torrente, P. Stoll, J. I. Pascual, K. J. Franke, W. Kuch. 2012-12-14. Ferromagnetic coupling of mononuclear Fe centers in a self-assembled metal-organic network on Au(111). https://doi.org/10.1103/physrevlett.109.267207

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