Illustrating double-slit interference: Yet another way

E. L. Cleveland

Huei Peng

We report observations of Cross-Double-Slit Experiment and Which-Path-Cross-Double-Slit experiment. Cross-Double-Slit apparatus contains two double-slit, where first double-slit is perpendicular to second double-slit. The first double-slit and the second double-slit generate not only their own interference pattern perpendicular to each other, but also generate “Cross-interference-patterns”. When we do which-way experiment with one of two double-slit, say first double-slit, then its interference pattern disappeared, i.e., photons behave as particles; but the second double-slit’s interference pattern and the cross-interference-pattern still exist; which implies an significant phenomenon that in the same experiment, photons behave as both wave and particle, which is first time caught on film. Thus we suggest to re-study wave-particle duality, which is the basic mystery of quantum mechanics. We postulate that the particle nature of photons is intrinsic; while the wave-like of photons is manifest-behavior.

Siddhant Das, Dirk-André Deckert, Leopold Kellers +2 more

Manpreet Kaur, Mandip Singh

Double-double-slit thought experiment provides profound insight on interference of quantum entangled particles. This paper presents a detailed experimental realisation of quantum double-double-slit thought experiment with momentum entangled photons and theoretical analysis of the experiment. Experiment is configured in such a way that photons are path entangled and each photon can reveal the which-slit path information of the other photon. As a consequence, single photon interference is suppressed. However, two-photon interference pattern appears if locations of detection of photons are correlated without revealing the which-slit path information. It is also shown experimentally and theoretically that two-photon quantum interference disappears when the which-slit path of a photon in the double-double-slit is detected.

Ian MacInnes, Andrew Donaldson

X.-J. Liu, Quan Miao, Faris Gel’mukhanov +6 more

Double-slit experiments illustrate proof for wave–particle complementarity. The essence of Einstein–Bohr's debate about wave–particle duality was whether the momentum transfer between a particle and a recoiling slit could mark the path, thus destroying the interference. We realized this recoiling double-slit gedanken experiment by resonant X-ray photoemission from molecular oxygen for geometries near equilibrium (coupled slits) and in a dissociative state far away from equilibrium (decoupled slits). Interference is observed in the former case, while the electron momentum transfer quenches the interference in the latter case.