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arXiv · 0812.4879

Nonequilibrium Critical Behavior for Electron Tunneling through Quantum Dots in an Aharonov-Bohm Circuit

Eran Sela·Ian Affleck
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Abstract

Double quantum dots can provide an experimental realization of the 2 impurity Kondo model which exhibits a non-Fermi liquid quantum critical point (QCP) at a special value of its parameters. We generalize our recent study of double quantum dots in series \cite{Sela08} to a parallel configuration with an Aharonov-Bohm flux. We present an exact universal result for the finite temperature and finite voltage conductance $G[V,T]$ along the crossover from the QCP to the low energy Fermi liquid phase. Compared to the series configuration, here generically $G[V,T] \ne G[-V,T]$, leading to current rectification.

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Eran Sela, Ian Affleck. 2008-12-29. Nonequilibrium Critical Behavior for Electron Tunneling through Quantum Dots in an Aharonov-Bohm Circuit. https://doi.org/10.1103/physrevb.79.125110

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