Room temperature p-induced surface ferromagnetism

Guntram Fischer; Nadiezhda Sanchez; Waheed A. Adeagbo; Martin Lüders; Zdzislawa Szotek; Walter M. Temmerman; Arthur Ernst; Wolfram Hergert; M. Carmen Muñoz

arXiv · 1105.2777

Room temperature p-induced surface ferromagnetism

Guntram Fischer·Nadiezhda Sanchez·Waheed A. Adeagbo·Martin Lüders·Zdzislawa Szotek·Walter M. Temmerman·Arthur Ernst·Wolfram Hergert·M. Carmen Muñoz

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Abstract

We prove a spontaneous magnetization of the oxygen-terminated ZnO (0001) surface by utilizing a multi-code, SIESTA and KKR, first-principles approach, involving both LSDA+U and selfinteraction corrections (SIC) to treat electron correlation effects. Critical temperatures are estimated from Monte Carlo simulations, showing that at and above 300 K the surface is thermodynamically stable and ferromagnetic. The observed half-metallicity and long-range magnetic order originate from the presence of p-holes in the valence band of the oxide. The mechanism is universal in ionic oxides and points to a new route for the design of ferromagnetic low dimensional systems.

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Guntram Fischer, Nadiezhda Sanchez, Waheed A. Adeagbo, Martin Lüders, Zdzislawa Szotek, Walter M. Temmerman, Arthur Ernst, Wolfram Hergert, M. Carmen Muñoz. 2011-05-13. Room temperature p-induced surface ferromagnetism. https://arxiv.org/abs/1105.2777

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