Efficient, high-density, carbon-based spinterfaces

F. Djeghloul; G. Garreau; M. Gruber; L. Joly; S. Boukari; J. Arabski; H. Bulou; F. Scheurer; F. Bertran; P. Le Fèvre; A. Taleb-Ibrahimi; W. Wulfhekel; E. Beaurepaire; S. Hajjar-Garreau; P. Wetzel; M. Bowen; W. Weber

arXiv · 1410.6901

Efficient, high-density, carbon-based spinterfaces

F. Djeghloul·G. Garreau·M. Gruber·L. Joly·S. Boukari·J. Arabski·H. Bulou·F. Scheurer·F. Bertran·P. Le Fèvre·A. Taleb-Ibrahimi·W. Wulfhekel·E. Beaurepaire·S. Hajjar-Garreau·P. Wetzel·M. Bowen·W. Weber

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Abstract

The research field of spintronics has sought, over the past 25 years and through several materials science tracks, a source of highly spin-polarized current at room temperature. Organic spinterfaces, which consist in an interface between a ferromagnetic metal and a molecule, represent the most promising track as demonstrated for a handful of interface candidates. How general is this effect? We deploy topographical and spectroscopic techniques to show that a strongly spin-polarized interface arises already between ferromagnetic cobalt and mere carbon atoms. Scanning tunneling microscopy and spectroscopy show how a dense semiconducting carbon film with a low band gap of about 0.4 eV is formed atop the metallic interface. Spin-resolved photoemission spectroscopy reveals a high degree of spin polarization at room temperature of carbon-induced interface states at the Fermi energy. From both our previous study of cobalt/phthalocyanine spinterfaces and present x-ray photoemission spectroscopy studies of the cobalt/carbon interface, we infer that these highly spin-polarized interface states arise mainly from sp2-bonded carbon atoms. We thus demonstrate the molecule-agnostic, generic nature of the spinterface formation.

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F. Djeghloul, G. Garreau, M. Gruber, L. Joly, S. Boukari, J. Arabski, H. Bulou, F. Scheurer, F. Bertran, P. Le Fèvre, A. Taleb-Ibrahimi, W. Wulfhekel, E. Beaurepaire, S. Hajjar-Garreau, P. Wetzel, M. Bowen, W. Weber. 2014-10-25. Efficient, high-density, carbon-based spinterfaces. https://arxiv.org/abs/1410.6901

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