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Quantum transport through double-dot Aharonov-Bohm interferometry in Coulomb blockade regime

Jing Ma·Bing Dong·X. L. Lei
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Abstract

Transport through two quantum dots laterally embedded in Aharonov-Bohm interferometry with infinite intradot and arbitrary interdot Coulomb repulsion is analyzed in the weak coupling and Coulomb blockade regime. By employing the modified quantum rate equations and the slave-boson approach, we establish a general dc current formula at temperatures higher than the Kondo temperature for the case that the spin degenerate levels of two dots are close to each other. We examine two simple examples for identical dots - no doubly occupied states and no empty state. In the former, completely destructive coherent transport and phase locking appear at magnetic flux $Φ=Φ_{0}/2$ and $Φ=0$ respectively; in the latter, partially coherent transport exhibits an oscillation with magnetic flux having a period of $Φ_0$.

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Jing Ma, Bing Dong, X. L. Lei. 2003-10-15. Quantum transport through double-dot Aharonov-Bohm interferometry in Coulomb blockade regime. https://doi.org/10.1140/epjb%2Fe2004-00014-4

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