Weak-value amplification: state of play

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.

7 pages, to appear in "Quantum Measurements and Quantum Metrology"

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Cited by in corpus (17)

• Approaching quantum-limited metrology with imperfect detectors by using weak-value amplification
• Weak value controversy
• Wavelength-scale errors in optical localization due to spin-orbit coupling of light
• Post-selected von Neumann measurement with Hermite-Gaussian and Laguerre-Gaussian pointer states
• On the novelty, efficacy, and significance of weak measurements for quantum tomography
• Unifying theory of quantum state estimation using past and future information
• Scheme and Experimental Demonstration of Fully Atomic Weak Value Amplification
• Adaptive weak-value amplification with adjustable postselection
• Achieving metrological precision limits through post-selection
• Statistical hypothesis testing by weak-value amplification: Proposal and evaluation
• Cost of postselection in decision theory
• Physical description of statistical hypothesis testing for a weak-value amplification experiment using a birefringent crystal
• Weak Particle Presence
• Weak values obtained from mass-energy equivalence
• Weak measurement amplification based on thermal noise effect
• Precision metrology of weak measurement with thermal state pointer
• The Informational Observer in Relational Quantum Mechanics