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Swapping entangled Kondo resonances in parallel-coupled double quantum dots

G. -M. Zhang·R. Lu·Z. -R. Liu·L. Yu
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Abstract

Strong electron and spin correlations are studied in parallel-coupled double quantum dots with interdot spin superexchange $J$. In the Kondo regime with {\it}{degenerate} dot energy levels, a coherent transport occurs at zero temperature, where two entangled (bonding and antibonding) resonances are formed near the Fermi energy. When increasing $J$ or the dot-lead parallel-coupling \QTR{it}{asymmetry} ratio $Γ_{2}/Γ_{1}$, a swap between two entangled resonances occurs and the line shapes of the linear conductance are interchanged. The zero-bias differential conductance shows a peak at the critical values. Such a peculiar effect with the virtue of many-body coherence may be useful in future quantum computing.

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G. -M. Zhang, R. Lu, Z. -R. Liu, L. Yu. 2004-03-25. Swapping entangled Kondo resonances in parallel-coupled double quantum dots. https://doi.org/10.1103/physrevb.72.073308

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