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arXiv · 0911.5139

Measuring small longitudinal phase shifts: weak measurements or standard interferometry?

Nicolas Brunner·Christoph Simon
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Abstract

Recently, weak measurements were used to measure small effects that are transverse to the propagation direction of a light beam. Here we address the question whether weak measurements are also useful for measuring small longitudinal phase shifts. We show that standard interferometry greatly outperforms weak measurements in a scenario involving a purely real weak value. However, we also present an interferometric scheme based on a purely imaginary weak value, combined with a frequency-domain analysis, which may have potential to outperform standard interferometry by several orders of magnitude.

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Nicolas Brunner, Christoph Simon. 2010-07-09. Measuring small longitudinal phase shifts: weak measurements or standard interferometry?. https://doi.org/10.1103/physrevlett.105.010405

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