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arXiv · 0706.1508

Sequential weak measurement

Graeme Mitchison·Richard Jozsa·Sandu Popescu
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Abstract

The notion of weak measurement provides a formalism for extracting information from a quantum system in the limit of vanishing disturbance to its state. Here we extend this formalism to the measurement of sequences of observables. When these observables do not commute, we may obtain information about joint properties of a quantum system that would be forbidden in the usual strong measurement scenario. As an application, we provide a physically compelling characterisation of the notion of counterfactual quantum computation.

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Graeme Mitchison, Richard Jozsa, Sandu Popescu. 2007-08-03. Sequential weak measurement. https://doi.org/10.1103/physreva.76.062105

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