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arXiv · 0906.4645

Co dimers on hexagonal carbon rings proposed as subnanometer magnetic storage bits

Ruijuan Xiao·Daniel Fritsch·Michael D. Kuz'min·Klaus Koepernik·Helmut Eschrig·Manuel Richter·Knut Vietze·Gotthard Seifert
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Abstract

It is demonstrated by means of density functional and ab-initio quantum chemical calculations, that transition metal - carbon systems have the potential to enhance the presently achievable area density of magnetic recording by three orders of magnitude. As a model system, Co_2-benzene with a diameter of 0.5 nm is investigated. It shows a magnetic anisotropy in the order of 0.1 eV per molecule, large enough to store permanently one bit of information at temperatures considerably larger than 4 K. A similar performance can be expected, if cobalt dimers are deposited on graphene or on graphite. It is suggested that the subnanometer bits can be written by simultaneous application of a moderate magnetic and a strong electric field.

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Ruijuan Xiao, Daniel Fritsch, Michael D. Kuz'min, Klaus Koepernik, Helmut Eschrig, Manuel Richter, Knut Vietze, Gotthard Seifert. 2009-06-25. Co dimers on hexagonal carbon rings proposed as subnanometer magnetic storage bits. https://doi.org/10.1103/physrevlett.103.187201

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