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Shot noise in self-assembled InAs quantum dots

A. Nauen·I. Hapke-Wurst·F. Hohls·U. Zeitler·R. J. Haug·K. Pierz
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Abstract

We investigate the noise properties of a GaAs-AlAs-GaAs tunneling structure with embedded self-assembled InAs quantum dots in the single-electron tunneling regime. We analyze the dependence of the relative noise amplitude of the shot noise on bias voltage. We observe a non-monotonic behaviour of the Fano-factor $α$ with an average value of $α\approx 0.8$ consistent with the asymmetry of the tunneling barriers. Reproducible fluctuations observed in $α$ can be attributed to the successive participation of more and more InAs quantum dots in the tunneling current.

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A. Nauen, I. Hapke-Wurst, F. Hohls, U. Zeitler, R. J. Haug, K. Pierz. 2002-07-10. Shot noise in self-assembled InAs quantum dots. https://doi.org/10.1103/physrevb.66.161303

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