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arXiv · 0708.0539

Transmission in double quantum dots in the Kondo regime: Quantum-critical transitions and interference effects

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

We study the transmission through a double quantum-dot system in the Kondo regime. An exact expression for the transmission coefficient in terms of fully interacting many-body Green's functions is obtained. By mapping the system into an effective Anderson impurity model, one can determine the transmission using numerical renormalization-group methods. The transmission exhibits signatures of the different Kondo regimes of the effective model, including an unusual Kondo phase with split peaks in the spectral function, as well as a pseudogapped regime exhibiting a quantum critical transition between Kondo and unscreened phases.

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Luis G. Dias da Silva, Nancy Sandler, Kevin Ingersent, Sergio E. Ulloa. 2007-08-07. Transmission in double quantum dots in the Kondo regime: Quantum-critical transitions and interference effects. https://doi.org/10.1016/j.physe.2007.08.098

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