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The Kondo Effect in the Unitary Limit

W. G. van der Wiel·S. De Franceschi·T. Fujisawa·J. M. Elzerman·S. Tarucha·L. P. Kouwenhoven
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Abstract

We observe a strong Kondo effect in a semiconductor quantum dot when a small magnetic field is applied. The Coulomb blockade for electron tunneling is overcome completely by the Kondo effect and the conductance reaches the unitary-limit value. We compare the experimental Kondo temperature with the theoretical predictions for the spin-1/2 Anderson impurity model. Excellent agreement is found throughout the Kondo regime. Phase coherence is preserved when a Kondo quantum dot is included in one of the arms of an Aharonov-Bohm ring structure and the phase behavior differs from previous results on a non-Kondo dot.

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W. G. van der Wiel, S. De Franceschi, T. Fujisawa, J. M. Elzerman, S. Tarucha, L. P. Kouwenhoven. 2000-09-26. The Kondo Effect in the Unitary Limit. https://doi.org/10.1126/science.289.5487.2105

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