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arXiv · 0904.0482

Fano-Kondo Spin Filter

A. C. Seridonio·F. M. Souza·J. Del Nero·I. A. Shelykh
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Abstract

We study spin-dependent conductance in a system composed of a ferromagnetic (FM) Scanning Tunneling Microscope (STM) tip coupled to a metallic host surface with an adatom. The Kondo resonance is taken into account via the Doniach-Sunjic spectral function. For short lateral tip-adatom distances and due to the interplay between Kondo physics, quantum interfering effects and the ferromagnetism of the tip, a spin-splitting of the Fano-Kondo line shape arises in the conductance. A strong enhancement of the Fano-Kondo profile for the majority spin component of the FM tip is observed. When the tip is placed on the adatom, this gives a conductance 100 % polarized for a particular range of bias voltage. The system thus can be used as a powerful generator of spin polarized currents.

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A. C. Seridonio, F. M. Souza, J. Del Nero, I. A. Shelykh. 2009-04-02. Fano-Kondo Spin Filter. https://doi.org/10.1016/j.physe.2009.05.006

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