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arXiv · 1009.6228

Graphene as a non-magnetic spin-current lens

F. S. M. Guimarães·A. T. Costa·R. B. Muniz·M. S. Ferreira
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Abstract

In spintronics, the ability to transport magnetic information often depends on the existence of a spin current traveling between two different magnetic objects acting as source and probe. A large fraction of this information never reaches the probe and is lost because the spin current tends to travel omni-directionally. We propose that a curved boundary between a gated and a non-gated region within graphene acts as an ideal lens for spin currents despite being entirely of non-magnetic nature. We show as a proof of concept that such lenses can be utilized to redirect the spin current that travels away from a source onto a focus region where a magnetic probe is located, saving a considerable fraction of the magnetic information that would be otherwise lost.

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F. S. M. Guimarães, A. T. Costa, R. B. Muniz, M. S. Ferreira. 2011-04-14. Graphene as a non-magnetic spin-current lens. https://doi.org/10.1088/0953-8984%2F23%2F17%2F175302

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