Erlangen 2018 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
Q: Fachverband Quantenoptik und Photonik
Q 33: Quantum Information (Concepts and Methods) III
Q 33.2: Vortrag
Dienstag, 6. März 2018, 14:30–14:45, K 1.019
Universality of weak values and its application to an efficient alignment method for interferometers — Jan Dziewior1,2, Lukas Knips1,2, Demitry Farfurnik3, •Katharina Senkalla1,2, Nimrod Benshalom3, Jonathan Efroni3, Jasmin Meinecke1,2, Shimshon Bar-Ad3, Harald Weinfurter1,2, and Lev Vaidman3 — 1Max-Planck-Institute for Quantum Optics, Garching 85748 — 2Department for Physics, Ludwig-Maximilians-University, Munich 80797 — 3Raymond and Beverly Sackler School of Physics and Astronomy, Tel-Aviv University, Tel-Aviv 69978
Weak values characterize the weak interactions of pre- and postselected quantum systems, in particular they provide a simple and universal description for different measurement pointers and observables. We demonstrate this universality by considering a photon in an interferometer with weak local interactions in one of its arms coupling to different degrees of freedom (DOF), like position x, momentum p, and polarization of the photon. We show theoretically and experimentally that different interactions in the same arm will all modify the pointer DOF in an universal way.
By considering misalignments of an interferometer as such a coupling to x and p we can provide an easy and efficient alignment method. We use the fact, that the centroid of the interference pattern is modified according to the weak value, which mainly depends on the phase, the relative intensity and the overlap of the two arms. Analyzing a single 2π phase scan taken by a single position sensing detector yields all necessary alignment parameters.