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arXiv · 1208.1371

Shot noise spectroscopy on a semiconductor quantum dot in the elastic and inelastic cotunneling regimes

Yuma Okazaki·Satoshi Sasaki·Koji Muraki
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Abstract

We report shot noise spectroscopy on a semiconductor quantum dot in a cotunneling regime. The DC conductance measurements show clear signatures of both elastic and inelastic cotunneling transport inside a Coulomb diamond. We observed Poissonian shot noise with the Fano factor $F\approx 1$ in the elastic cotunneling regime, and super-Poissonian Fano factor $1<F<3$ in the inelastic cotunneling regime. The differences in the value of the Fano factor between elastic and inelastic processes reveal the microscopic mechanisms involved in the cotunneling transport.

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Yuma Okazaki, Satoshi Sasaki, Koji Muraki. 2013-01-09. Shot noise spectroscopy on a semiconductor quantum dot in the elastic and inelastic cotunneling regimes. https://doi.org/10.1103/physrevb.87.041302

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