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Zero-field Kondo splitting and quantum-critical transition in double quantum dots

Luis Dias da Silva·Nancy Sandler·Kevin Ingersent·Sergio Ulloa
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Abstract

Double quantum dots offer unique possibilities for the study of many-body correlations. A system containing one Kondo dot and one effectively noninteracting dot maps onto a single-impurity Anderson model with a structured (nonconstant) density of states. Numerical renormalization-group calculations show that while band filtering through the resonant dot splits the Kondo resonance, the singlet ground state is robust. The system can also be continuously tuned to create a pseudogapped density of states and access a quantum critical point separating Kondo and non-Kondo phases.

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Luis Dias da Silva, Nancy Sandler, Kevin Ingersent, Sergio Ulloa. 2006-08-03. Zero-field Kondo splitting and quantum-critical transition in double quantum dots. https://doi.org/10.1103/physrevlett.97.096603

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