Kondo effect in a semiconductor quantum dot coupled to ferromagnetic electrodes

The University of Tokyo, Tōkyō, Japan
Applied Physics Letters (Impact Factor: 3.3). 12/2007; 91(23):232105. DOI: 10.1063/1.2820445
Source: arXiv


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. Comment: 4 pages, 3 figures

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