Europhys. Lett.
Volume 67, Number 3, August 2004
Page(s) 439 - 445
Section Condensed matter: electronic structure, electrical, magnetic, and optical properties
Published online 01 July 2004
Europhys. Lett., 67 (3), pp. 439-445 (2004)
DOI: 10.1209/epl/i2004-10084-x

Multi-terminal transport through a quantum dot in the Coulomb-blockade regime

R. Leturcq1, D. Graf1, T. Ihn1, K. Ensslin1, D. D. Driscoll2 and A. C. Gossard2

1  Solid State Physics Laboratory, ETH Zürich - 8093 Zürich, Switzerland
2  Materials Department, University of California - Santa Barbara, CA 93106, USA

(Received 10 May 2004; accepted 28 May 2004)

Three-terminal tunnelling experiments on quantum dots in the Coulomb-blockade regime allow a quantitative determination of the coupling strength of individual quantum states to the leads. Exploiting this insight, we have observed independent fluctuations of the coupling strengths as a function of electron number and magnetic field due to changes in the shape of the wave function in the dot. Such a detailed understanding and control of the dot-lead coupling can be extended to more complex systems such as coupled dots, and are essential for building functional quantum electronic systems.

73.23.Hk - Coulomb blockade; single-electron tunneling.
73.63.Kv - Quantum dots.

© EDP Sciences 2004