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arXiv · 1409.4094

Crossover between strong and weak measurement in interacting many-body systems

Iliya Esin·Alessandro Romito·Ya. M. Blanter·Yuval Gefen
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Abstract

Measurements with variable system-detector interaction strength, ranging from weak to strong, have been recently reported in a number of electronic nanosystems. In several such instances many-body effects play a significant role. Here we consider the weak--to--strong crossover for a setup consisting of an electronic Mach-Zehnder interferometer, where a second interferometer is employed as a detector. In the context of a conditional which-path protocol, we define a generalized conditional value (GCV), and determine its full crossover between the regimes of weak and strong (projective) measurement. We find that the GCV has an oscillatory dependence on the system-detector interaction strength. These oscillations are a genuine many-body effect, and can be experimentally observed through the voltage dependence of cross current correlations.

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Iliya Esin, Alessandro Romito, Ya. M. Blanter, Yuval Gefen. 2014-09-14. Crossover between strong and weak measurement in interacting many-body systems. https://arxiv.org/abs/1409.4094

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