Gate-controlled spin-splitting in quantum dots with ferromagnetic leads in the Kondo regime
Abstract
The effect of a gate voltage () on the spin-splitting of an electronic level in a quantum dot (QD) attached to ferromagnetic leads is studied in the Kondo regime using a generalized numerical renormalization group technique. We find that the -dependence of the QD level spin-splitting strongly depends on the shape of the density of states (DOS). For one class of DOS shapes there is nearly no -dependence, for another, can be used to control the magnitude and sign of the spin-splitting, which can be interpreted as a local exchange magnetic field. We find that the spin-splitting acquires a new type of logarithmic divergence. We give an analytical explanation for our numerical results and explain how they arise due to spin-dependent charge fluctuations.
Keywords
Cite
@article{arxiv.cond-mat/0406323,
title = {Gate-controlled spin-splitting in quantum dots with ferromagnetic leads in the Kondo regime},
author = {J. Martinek and M. Sindel and L. Borda and J. Barnas and R. Bulla and J. König and G. Schön and S. Maekawa and J. von Delft},
journal= {arXiv preprint arXiv:cond-mat/0406323},
year = {2007}
}
Comments
4 pages, 2 figures