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Science 22 September 2000:
Vol. 289. no. 5487, pp. 2105 - 2108
DOI: 10.1126/science.289.5487.2105
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Reports

The Kondo Effect in the Unitary Limit

W. G. van der Wiel,1* S. De Franceschi,1 T. Fujisawa,2 J. M. Elzerman,1 S. Tarucha,23 L. P. Kouwenhoven1

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.

1 Department of Applied Physics, Delft Institute for Microelectronics and Submicrontechnology, and ERATO Mesoscopic Correlation Project, Delft University of Technology, Post Office Box 5046, 2600 GA Delft, Netherlands.
2 NTT Basic Research Laboratories, Atsugi-shi, Kanagawa 243-0198, Japan.
3 ERATO Mesoscopic Correlation Project, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan.
*   To whom correspondence should be addressed. E-mail: wilfred{at}qt.tn.tudelft.nl

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THIS ARTICLE HAS BEEN CITED BY OTHER ARTICLES:
Controlling the Kondo Effect of an Adsorbed Magnetic Ion Through Its Chemical Bonding.
A. Zhao, Q. Li, L. Chen, H. Xiang, W. Wang, S. Pan, B. Wang, X. Xiao, J. Yang, J. G. Hou, et al. (2005)
Science 309, 1542-1544
   Abstract »    Full Text »    PDF »
The Kondo Effect in an Artificial Quantum Dot Molecule.
H. Jeong, A. M. Chang, and M. R. Melloch (2001)
Science 293, 2221-2223
   Abstract »    Full Text »    PDF »


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