Anomalous weak values via a single photon detection

Abstract

Is it possible that a measurement of a spin component of a spin-1/2 particle yields the value 100? In 1988 Aharonov, Albert and Vaidman argued that upon pre- and postselection of particular spin states, weakening the coupling of a standard measurement procedure ensures this paradoxical result. This theoretical prediction, called weak value, was realized in numerous experiments, but its meaning remains very controversial, since its "anomalous" nature, i.e. the possibility to exceed the eigenvalues range, as well as its "quantumness" are debated. We address these questions by presenting the first experiment measuring anomalous weak values with just a single click, without any statistics. The measurement uncertainty is significantly smaller than the gap between the measured weak value and the nearest eigenvalue. Beyond clarifying the meaning of weak values, this result represents a breakthrough in understanding quantum measurement foundations, paving the way to further applications of weak values to quantum photonics.

arXiv commentRevised version to appear in Light: Science & Applications

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Cited by in corpus (15)

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• Single-pair measurement of the Bell parameter
• Progress and Perspectives on Weak-value Amplification
• Dimension-independent weak value estimation via controlled SWAP operations
• Experimental Test of Nonlocality Limits from Relativistic Independence
• Exploring postselection-induced quantum phenomena with time-bidirectional state formalism
• General approach of weak-to-strong measurement transition for Fock-state-based pointer states
• Obtaining a Single-Photon Weak Value from Experiments using a Strong (Many-Photon) Coherent State
• Performance advantage of protective quantum measurements
• Sequential unsharp measurement of photon polarization
• Spatio-Temporal Weak Measurement of Chiral Ultra short Laser Pulse
• Testing time order and Leggett-Garg inequalities with noninvasive measurements on public quantum computers
• Time Derivatives of Weak Values