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arXiv · 1403.5897

Measuring cotunneling in its wake

Oded Zilberberg·Assaf Carmi·Alessandro Romito
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Abstract

We introduce a rate formalism to treat classically forbidden electron transport through a quantum dot (cotunneling) in the presence of a coupled measurement device. We demonstrate this formalism for a toy model case of cotunneling through a single-level dot while being coupled to a strongly pinched-off quantum point contact (QPC). We find that the detector generates three types of back-action: the measurement collapses the coherent transport through the virtual state, but at the same time allows for QPC-assisted incoherent transport, and widens the dot level. Last, we obtain the measured cotunneling time from the cross correlation between dot and QPC currents.

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Oded Zilberberg, Assaf Carmi, Alessandro Romito. 2014-03-24. Measuring cotunneling in its wake. https://doi.org/10.1103/physrevb.90.205413

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