Contact-induced spin polarization in carbon nanotubes
نویسندگان
چکیده
Motivated by the possibility of combining spintronics with molecular structures, we investigate the conditions for the appearance of spin polarization in low-dimensional tubular systems by contacting them to a magnetic substrate. We derive a set of general expressions describing the charge transfer between the tube and the substrate and the relative energy costs. The mean-field solution of the general expressions provides an insightful formula for the induced spin polarization. Using a tight-binding model for the electronic structure we are able to estimate the magnitude and the stability of the induced moment. This indicates that a significant magnetic moment in carbon nanotubes can be observed.
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