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Tristability in a non-equilibrium double-quantum-dot in Kondo regime

Gustavo A. Lara·Pedro A. Orellana·Enrique V. Anda
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Abstract

Electron tunneling through a non-equilibrium double quantum dot in the Kondo regime is studied. In the region of negative differential resistance, it is shown that this system possesses a complex response to the applied potential characterized by a tristable solution for the current. Increasing the applied potential or reducing the inter-dot coupling, the system goes through a transition from a coherent inter-dot regime to an incoherent one. The different nature of the solutions are characterized and it is shown that the effects of the asymmetry in the dot-lead coupling can be used to control the region of multistability. The mean-field slave-boson formalism is used to obtain the solution of the problem.

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Gustavo A. Lara, Pedro A. Orellana, Enrique V. Anda. 2002-11-22. Tristability in a non-equilibrium double-quantum-dot in Kondo regime. https://doi.org/10.1016/s0038-1098(02)00766-4

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