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arXiv · 1406.4762

Projective versus weak measurement of charge in a mesoscopic conductor

David Oehri·Andrei V. Lebedev·Gordey B. Lesovik·Gianni Blatter
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Abstract

We study the charge dynamics of a quantum dot as measured by a nearby quantum point contact probing the dot via individual single-particle wave packets. We contrast the two limiting cases of weak and strong system--detector coupling exerting vanishing and strong back-action on the system and analyze the resulting differences in the charge-charge correlator. Extending the study to multiple projective measurements modelling a continuous strong measurement, we identify a transition from a charge dynamics dominated by the system's properties to a universal dynamics governed by the measurement.

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David Oehri, Andrei V. Lebedev, Gordey B. Lesovik, Gianni Blatter. 2014-06-18. Projective versus weak measurement of charge in a mesoscopic conductor. https://doi.org/10.1103/physrevb.90.075312

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