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Quantum dots with even number of electrons: Kondo effect in a finite magnetic field

M. Pustilnik·Y. Avishai·K. Kikoin
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Abstract

We study a small spin-degenerate quantum dot with even number of electrons, weakly connected by point contacts to the metallic electrodes, and subject to an external magnetic field. If the Zeeman energy B is equal to the single-particle level spacing $Δ$ in the dot, the ground state of the dot becomes doubly degenerate, and the system exhibits Kondo effect, despite the fact that B exceeds by far the Kondo temperature $T_{K}$. A possible realization of this in tunneling experiments is discussed.

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M. Pustilnik, Y. Avishai, K. Kikoin. 1999-10-18. Quantum dots with even number of electrons: Kondo effect in a finite magnetic field. https://doi.org/10.1103/physrevlett.84.1756

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