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arXiv · 2103.15711

Protective Measurement -- a new quantum measurement paradigm: detailed description of the first realisation

Enrico Rebufello·Fabrizio Piacentini·Alessio Avella·Rudi Lussana·Federica Villa·Alberto Tosi·Marco Gramegna·Giorgio Brida·Eliahu Cohen·Lev Vaidman·Ivo Pietro Degiovanni·Marco Genovese
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Abstract

We present a detailed description of the experiment realising for the first time a protective measurement, a novel measurement protocol which combines weak interactions with a ``protection mechanism'' preserving the measured state coherence during the whole measurement process. Furthermore, protective measurement allows finding the expectation value of an observable, i.e. an inherently statistical quantity, by measuring a single particle, without the need of any statistics. This peculiar property, in sharp contrast with the framework of traditional (projective) quantum measurement, might constitute a groundbreaking advance for several quantum technology related fields.

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Enrico Rebufello, Fabrizio Piacentini, Alessio Avella, Rudi Lussana, Federica Villa, Alberto Tosi, Marco Gramegna, Giorgio Brida, Eliahu Cohen, Lev Vaidman, Ivo Pietro Degiovanni, Marco Genovese. 2021-03-29. Protective Measurement -- a new quantum measurement paradigm: detailed description of the first realisation. https://doi.org/10.3390/app11094260

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