Konrad Banaszek from University of Warsaw is going to visit us from Monday 27 Feb (afternoon) to Thursday 2 Mar 2017.
On Tuesday, Feb 28th, 12 AM Konrad is going to deliver a seminar entitled
Restoring quantum enhancement in two-photon interferometry
We analyze the interplay between one- and two-photon interference in a Mach-Zehnder interferometer fed with partly distinguishable photon pairs. We show that deleterious effects of residual distinguishability in one, experimentally inaccessible degree of freedom can be alleviated by engineering another, fully controllable degree of freedom. As a result, sub-shot-noise precision of a local phase measurement can be restored in the operating regime where standard two-photon interference provides vanishing phase sensitivity. Theoretical results are illustrated with an experiment utilizing spatially resolved detection of photon pairs prepared in carefully engineered transverse modes to overcome effects of residual distinguishability in the spectral domain.
M. Jachura et al Nature Comm 7, 11411 (2016)