Triple photons and triple slits, a new frontier in quantum mechanics tests

We will present our recent results in the generation of triple photons as well as triple slits, both providing interesting perspectives on the foundations of quantum mechanics and quantum optics. The creation of correlated triple photons [1] is a highly desirable process for research on quantum optics, novel states of three-photon entanglement, and applications in quantum information processing. It was proposed over 20 years ago, but considered impossible to perform given the low conversion efficiencies in non-linear optics. We recently managed to solve the technical challenges, and demonstrate a source for correlated photon triplets. Strikingly, the interferences of single photons passing through a triple slit can be useful for experimental verification of Bora´s rule, which is at the heart of the formalism of quantum mechanics. We will illustrate the background of the argumentation, and show the elegant experimental setup, which allows this direct test of Born´s rule[2].