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arXiv · 0801.1814

Weak measurement: Effect of the detector dynamics

Antonio Di Lorenzo·J. Carlos Egues
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Abstract

A general approach to the measurement of an observable with pre- and post-selection is presented. The limit of weak measurement is studied in detail, and it is shown that the phase of the probe, including a Hamiltonian contribution to it, gives rise to observable effects, since the coherence of the probe is essential for the concept of complex weak value to be meaningful. As a particular example, the measurement of a spin component is considered. We find that the contribution of the imaginary part of the weak value is sizeable in this case.

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Antonio Di Lorenzo, J. Carlos Egues. 2008-04-18. Weak measurement: Effect of the detector dynamics. https://doi.org/10.1103/physreva.77.042108

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