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Frontiers in Optics

Theory and experiment for resource-efficient joint weak- measurement

Aldo C. Martinez-Becerril, Gabriel Bussières, Davor Curic, Lambert Giner, Raphael A. Abrahão, Jeff S. Lundeen

Published Jan 1, 2021• 0 citations
Publisher

Abstract

Weak measurement allows the measurement of two incompatible observables, a ‘joint weak-measurement’ (JWM). Until now, JWM uses one read-out, a separate system, per observable. We demonstrate a JWM technique which requires only one read-out.
DOI
10.1364/fio.2021.fth6d.3

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One of the most intriguing aspects of quantum mechanics is the impossibility of measuring at the same time observables corresponding to noncommuting operators, because of quantum uncertainty. This impossibility can be partially relaxed when considering joint or sequential weak value evaluation. Indeed, weak value measurements have been a real breakthrough in the quantum measurement framework that is of the utmost interest from both a fundamental and an applicative point of view. In this Letter, we show how we realized for the first time a sequential weak value evaluation of two incompatible observables using a genuine single-photon experiment. These (sometimes anomalous) sequential weak values revealed the single-operator weak values, as well as the local correlation between them.
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