Anomalous weak values via a single photon detection
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 1 . Th...
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Published in | Light, science & applications Vol. 10; no. 1; p. 106 |
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Main Authors | , , , , , , , , , |
Format | Journal Article |
Language | English |
Published |
London
Nature Publishing Group UK
25.05.2021
Springer Nature B.V Nature Publishing Group |
Subjects | |
Online Access | Get full text |
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Summary: | 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
1
. This theoretical prediction, called
weak value
, was realised in numerous experiments
2
–
9
, but its meaning remains very controversial
10
–
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, since its “anomalous” nature, i.e., the possibility to exceed the eigenvalue spectrum, as well as its “quantumness” are debated
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–
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. We address these questions by presenting the first experiment measuring anomalous weak values with just a single click, without the need for statistical averaging. 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, demonstrating their non-statistical, single-particle nature, this result represents a breakthrough in understanding the foundations of quantum measurement, showing unprecedented measurement capability for further applications of weak values to quantum photonics. |
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Bibliography: | SourceType-Other Sources-1 content type line 63 ObjectType-Correspondence-1 |
ISSN: | 2047-7538 2095-5545 2047-7538 |
DOI: | 10.1038/s41377-021-00539-0 |