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A widely tunable few electron droplet

A. K. Huettel·K. Eberl·S. Ludwig
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Abstract

Quasi-static transport measurements are employed to characterize a few electron quantum dot electrostatically defined in a GaAs/AlGaAs heterostructure. The gate geometry allows observations on one and the same electron droplet within a wide range of coupling strengths to the leads. The weak coupling regime is described by discrete quantum states. At strong interaction with the leads Kondo phenomena are observed as a function of a magnetic field. By varying gate voltages the electron droplet can, in addition, be distorted into a double quantum dot with a strong interdot tunnel coupling while keeping track of the number of trapped electrons.

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A. K. Huettel, K. Eberl, S. Ludwig. 2007-02-28. A widely tunable few electron droplet. https://doi.org/10.1088/0953-8984%2F19%2F23%2F236202

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