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arXiv · 1410.6252

Weak-value amplification: state of play

George C. Knee·Joshua Combes·Christopher Ferrie·Erik M. Gauger
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Abstract

Weak values arise in quantum theory when the result of a weak measurement is conditioned on a subsequent strong measurement. The majority of the trials are discarded, leaving only very few successful events. Intriguingly those can display a substantial signal amplification. This raises the question of whether weak values carry potential to improve the performance of quantum sensors, and indeed a number of impressive experimental results suggested this may be the case. By contrast, recent theoretical studies have found the opposite: using weak-values to obtain an amplification generally worsens metrological performance. This survey summarises the implications of those studies, which call for a reappraisal of weak values' utility and for further work to reconcile theory and experiment.

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George C. Knee, Joshua Combes, Christopher Ferrie, Erik M. Gauger. 2014-10-23. Weak-value amplification: state of play. https://doi.org/10.1515/qmetro-2016-0006

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