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arXiv · 0705.2420

Bimodal Counting Statistics in Single Electron Tunneling through a Quantum Dot

C. Fricke·F. Hohls·W. Wegscheider·R. J. Haug
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Abstract

We explore the full counting statistics of single electron tunneling through a quantum dot using a quantum point contact as non-invasive high bandwidth charge detector. The distribution of counted tunneling events is measured as a function of gate and source-drain-voltage for several consecutive electron numbers on the quantum dot. For certain configurations we observe super-Poissonian statistics for bias voltages at which excited states become accessible. The associated counting distributions interestingly show a bimodal characteristic. Analyzing the time dependence of the number of electron counts we relate this to a slow switching between different electron configurations on the quantum dot.

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C. Fricke, F. Hohls, W. Wegscheider, R. J. Haug. 2007-05-16. Bimodal Counting Statistics in Single Electron Tunneling through a Quantum Dot. https://doi.org/10.1103/physrevb.76.155307

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