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arXiv · 1508.06548

Unconventional magnetisation texture in graphene / cobalt hybrids

A. D. Vu·J. Coraux·G. Chen·A. T. N'Diaye·A. K. Schmid·N. Rougemaille
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Abstract

Magnetic domain structure and spin-dependent reflectivity measurements on cobalt thin films intercalated at the graphene / Ir(111) interface are investigated using spin-polarised low-energy electron microscopy. We find that graphene-covered cobalt films have surprising magnetic properties. Vectorial imaging of magnetic domains reveals an unusually gradual thickness-dependent spin reorientation transition, in which magnetisation rotates from out-of-the-film plane to the in-plane direction by less than 10$^\circ$ per cobalt monolayer. During this transition, cobalt films have a meandering spin texture, characterised by a complex, three-dimensional, wavy magnetisation pattern. In addition, spectroscopy measurements indicate that the electronic band structure of the unoccupied states is essentially spin-independent already a few electron-Volts above the vacuum level. These properties strikingly differ from those of pristine cobalt films and could open new prospects in surface magnetism.

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A. D. Vu, J. Coraux, G. Chen, A. T. N'Diaye, A. K. Schmid, N. Rougemaille. 2015-08-26. Unconventional magnetisation texture in graphene / cobalt hybrids. https://arxiv.org/abs/1508.06548

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