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Kondo effect in quantum dots coupled to ferromagnetic leads

J. Martinek·Y. Utsumi·H. Imamura·J. Barnas·S. Maekawa·J. König·G. Schön
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Abstract

We study the Kondo effect in a quantum dot which is coupled to ferromagnetic leads and analyse its properties as a function of the spin polarization of the leads. Based on a scaling approach we predict that for parallel alignment of the magnetizations in the leads the strong-coupling limit of the Kondo effect is reached at a finite value of the magnetic field. Using an equation-of-motion technique we study nonlinear transport through the dot. For parallel alignment the zero-bias anomaly may be split even in the absence of an external magnetic field. For antiparallel spin alignment and symmetric coupling, the peak is split only in the presence of a magnetic field, but shows a characteristic asymmetry in amplitude and position.

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J. Martinek, Y. Utsumi, H. Imamura, J. Barnas, S. Maekawa, J. König, G. Schön. 2004-01-29. Kondo effect in quantum dots coupled to ferromagnetic leads. https://doi.org/10.1103/physrevlett.91.127203

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