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arXiv · 1804.05400

Universality of local weak interactions and its application for interferometric alignment

Jan Dziewior·Lukas Knips·Demitry Farfurnik·Katharina Senkalla·Nimrod Benshalom·Jonathan Efroni·Jasmin Meinecke·Shimshon Bar-Ad·Harald Weinfurter·Lev Vaidman
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Abstract

The modification of the effect of interactions of a particle as a function of its pre- and postselected states is analyzed theoretically and experimentally. The universality property of this modification in the case of local interactions of a spatially pre- and postselected particle has been found. It allowed to define an operational approach for characterization of the presence of a quantum particle in a particular place: the way it modifies the effect of local interactions. The experiment demonstrating this universality property provides an efficient interferometric alignment method, in which the beam on a single detector throughout one phase scan yields all misalignment parameters.

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Jan Dziewior, Lukas Knips, Demitry Farfurnik, Katharina Senkalla, Nimrod Benshalom, Jonathan Efroni, Jasmin Meinecke, Shimshon Bar-Ad, Harald Weinfurter, Lev Vaidman. 2018-04-15. Universality of local weak interactions and its application for interferometric alignment. https://doi.org/10.1073/pnas.1812970116

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