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arXiv · 0809.4304

Nonequilibrium Transport through Double Quantum Dots: Exact Results near Quantum Critical Point

Eran Sela·Ian Affleck
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Abstract

We study a double quantum dot in the regime where each dot carries a spin-1/2. This system is described by the 2-impurity Kondo model, having a non-Fermi liquid fixed point for a critical value of the inter-impurity coupling. The Hamiltonian describing the vicinity of the critical point, including the relevant potential scattering perturbations, can be cast in quadratic form. This allows us to predict a universal scaling function for the finite temperature nonlinear conductance along the crossover from the critical point to the surrounding stable fixed points.

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Eran Sela, Ian Affleck. 2008-09-25. Nonequilibrium Transport through Double Quantum Dots: Exact Results near Quantum Critical Point. https://doi.org/10.1103/physrevlett.102.047201

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