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Out-of-equilibrium Kondo effect in Double Quantum Dots

Ramon Aguado·David C. Langreth
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Abstract

The out-of-equilibrium transport properties of a double quantum dot system in the Kondo regime are studied theoretically by means of a two-impurity Anderson hamiltonian with interimpurity hopping. The hamiltonian is solved by means of a non-equilibrium generalization of the slave-boson mean-field theory. It is demonstrated that measurements of the differential conductance dI/dV, for the appropriate values of voltages and tunneling couplings, can give a direct observation of the coherent superposition between the many-body Kondo states of each dot. For large voltages and arbitrarily large interdot tunneling, there is a critical voltage above which the physical behaviour of the system is again that of two decoupled quantum dots, i.e two Kondo singularities pinned at each chemical potential.

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Ramon Aguado, David C. Langreth. 2000-06-23. Out-of-equilibrium Kondo effect in Double Quantum Dots. https://doi.org/10.1103/physrevlett.85.1946

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