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arXiv · 1202.4273

Counting statistics in an InAs nanowire quantum dot with a vertically coupled charge detector

Theodore Choi·Thomas Ihn·Silke Schön·Klaus Ensslin
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Abstract

A gate-defined quantum dot in an InAs nanowire is fabricated on top of a quantum point contact realized in a two-dimensional electron gas. The strong coupling between these two quantum devices is used to perform time-averaged as well as time-resolved charge detection experiments for electron flow through the quantum dot. We demonstrate that the Fano factor describing shot noise or time-correlations in single-electron transport depends in the theoretically expected way on the asymmetry of the tunneling barriers even in a regime where the thermal energy $k_\mathrm{B}T$ is comparable to the single-particle level spacing in the dot.

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Theodore Choi, Thomas Ihn, Silke Schön, Klaus Ensslin. 2012-02-20. Counting statistics in an InAs nanowire quantum dot with a vertically coupled charge detector. https://doi.org/10.1063/1.3687198

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