Using a laterally-fabricated quantum-dot (QD) spin-valve device, we experimentally study the Kondo effect in the electron transport through a semiconductor QD with an odd number of electrons (N). In a parallel magnetic configuration of the ferromagnetic electrodes, the Kondo resonance at N = 3 splits clearly without external magnetic fields. With applying magnetic fields (B), the splitting is gradually reduced, and then the Kondo effect is almost restored at B = 1.2 T. This means that, in the Kondo regime, an inverse effective magnetic field of B ~ 1.2 T can be applied to the QD in the parallel magnetic configuration of the ferromagnetic electrodes.
@article{arxiv.0711.2124,
title = {Kondo effect in a semiconductor quantum dot coupled to ferromagnetic electrodes},
author = {K. Hamaya and M. Kitabatake and K. Shibata and M. Jung and M. Kawamura and K. Hirakawa and T. Machida and T. Taniyama and S. Ishida and Y. Arakawa},
journal= {arXiv preprint arXiv:0711.2124},
year = {2009}
}