Electron Cotunneling in a Semiconductor Quantum Dot

S. De Franceschi; S. Sasaki; J. M. Elzerman; W. G. van der Wiel; S. Tarucha; L. P. Kouwenhoven

doi:10.1103/PhysRevLett.86.878

Electron Cotunneling in a Semiconductor Quantum Dot

S. De Franceschi, S. Sasaki, J. M. Elzerman, W. G. van der Wiel, S. Tarucha, and L. P. Kouwenhoven

Phys. Rev. Lett. 86, 878 – Published 29 January 2001

Abstract

We report transport measurements on a semiconductor quantum dot with a small number of confined electrons. In the Coulomb blockade regime, conduction is dominated by cotunneling processes. These can be either elastic or inelastic, depending on whether they leave the dot in its ground state or drive it into an excited state, respectively. We are able to discriminate between these two contributions and show that inelastic events can occur only if the applied bias exceeds the lowest excitation energy. Implications to energy-level spectroscopy are discussed.

Received 27 July 2000

DOI:https://doi.org/10.1103/PhysRevLett.86.878

Authors & Affiliations

S. De Franceschi¹, S. Sasaki², J. M. Elzerman¹, W. G. van der Wiel¹, S. Tarucha^2,3, and L. P. Kouwenhoven¹

¹Department of Applied Physics, DIMES, and ERATO Mesoscopic Correlation Project, Delft University of Technology, P.O. Box 5046, 2600 GA Delft, The Netherlands
²NTT Basic Research Laboratories, Atsugi-shi, Kanagawa 243-0198, Japan
³ERATO Mesoscopic Correlation Project, University of Tokyo, Bunkyo-ku, Tokyo 113-0033, Japan