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Dicke Effect in the Tunnel Current through two Double Quantum Dots

T. Vorrath·T. Brandes
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Abstract

We calculate the stationary current through two double quantum dots which are interacting via a common phonon environment. Numerical and analytical solutions of a master equation in the stationary limit show that the current can be increased as well as decreased due to a dissipation mediated interaction. This effect is closely related to collective, spontaneous emission of phonons (Dicke super- and subradiance effect), and the generation of a `cross-coherence' with entanglement of charges in singlet or triplet states between the dots. Furthermore, we discuss an inelastic `current switch' mechanism by which one double dot controls the current of the other.

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T. Vorrath, T. Brandes. 2003-05-19. Dicke Effect in the Tunnel Current through two Double Quantum Dots. https://doi.org/10.1103/physrevb.68.035309

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