Review of recent experimental progress in foundations of quantum mechanics and quantum information achieved in parametric downconversion experiments at IENGF

We review some recent experimental progress concerning foundations of quantum mechanics and quantum information obtained in the Carlo Novero Quantum Optics Laboratory at IENGF. After a short presentation of our polarization-entangled photon source (based on precise superposition of two type I PDC emissions) and of the results obtained with it, we describe in more detail an innovative double slit experiment where two degenerate photons produced by PDC are each sent to a specific slit. Beyond representing an interesting example of the relation between the visibility of interference and welcher Weg knowledge, this configuration has been suggested for testing de Broglie-Bohm theory (dBB) against standard quantum mechanics (SQM). Our results perfectly fit SQM results but disagree with dBB predictions. Then, we discuss a recent experiment addressed at clarifying the issue of which wave-particle observables are really to be considered when discussing wave-particle duality. This experiments realizes the theoretical proposal of Agarwal et al., overcoming the limitations of a previous experiment. Finally, we hint at the realization of a high-intensity high-spectral-selectivity PDC source to be used for quantum information studies.