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Tunable Non-local Spin Control in a Coupled Quantum Dot System

N. J. Craig·J. M. Taylor·E. A. Lester·C. M. Marcus·M. P. Hanson·A. C. Gossard
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Abstract

The effective interaction between magnetic impurities in metals that can lead to various magnetic ground states often competes with a tendency for electrons near impurities to screen the local moment (Kondo effect). The simplest system exhibiting the richness of this competition, the two-impurity Kondo system, is here realized experimentally in the form of two quantum dots coupled through an open conducting region. We demonstrate non-local spin control by suppressing and splitting Kondo resonances in one quantum dot by changing electron number and coupling of the other dot. Results suggest an approach to non-local spin control relevant to quantum information processing.

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N. J. Craig, J. M. Taylor, E. A. Lester, C. M. Marcus, M. P. Hanson, A. C. Gossard. 2004-04-25. Tunable Non-local Spin Control in a Coupled Quantum Dot System. https://doi.org/10.1126/science.1095452

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