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Frontiers in Optics

Experimental Demonstration of Conditional Weak Measurement and Its Use on Incompatible Observables

Thomas J. Bailey, Raphael A. Abrahão, Jeff S. Lundeen

Published Jan 1, 2021• 0 citations
Publisher

Abstract

We experimentally demonstrate a method to find the joint value of incompatible observables using two successive weak measurements, where the result of the second is conditional on the first.
DOI
10.1364/fio.2021.jth5a.2

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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.