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Quantum Transport and Integrability of the Anderson Model for a Quantum Dot with Multiple Leads

Sam Young Cho·Huan-Qiang Zhou·Ross H. McKenzie
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Abstract

We show that an Anderson Hamiltonian describing a quantum dot connected to multiple leads is integrable. A general expression for the non-linear conductance is obtained by combining the Bethe ansatz exact solution with Landauer-Büttiker theory. In the Kondo regime, a closed form expression is given for the matrix conductance at zero temperature and when all the leads are close to the symmetric point. A bias-induced splitting of the Kondo resonance is possible for three or more leads. Specifically, for $N$ leads, with each at a different chemical potential, there can be $N-1$ Kondo peaks in the conductance.

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Sam Young Cho, Huan-Qiang Zhou, Ross H. McKenzie. 2003-02-05. Quantum Transport and Integrability of the Anderson Model for a Quantum Dot with Multiple Leads. https://doi.org/10.1103/physrevb.68.125327

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