Quantum interferometry via temporal quantum erasing

Quantum interferometry, encompassing a plethora of techniques involving interference from single to multiple photons, to entangled photons on two or more degrees of freedom, is an extremely enticing research field with solid applicability stretching beyond the well-known quantum cryptography (quantum key distribution), proving valuable both in fundamental physics and metrology as well as in biosensing and in the study of chemical properties of fragile materials. If, from one side, it cannot ensure the sensitivity levels achievable with bright source interferometry, on the other side allows to extract the maximum possible amount of information carried by each single photon or entangled pair, ensuring an extremely sensitive and non-degrading approach to imaging, tomography, and precision metrology. Moreover, quantum interferometry allows investigations on quantum-relativistic crosstalk that are precluded to its bright source counterpart, which is the most common technique currently employed to approach relativistic tests. In this proceeding is discussed one of the main active research lines investigated by the Quantum Research Group within the Italian Space Agency, highlighting its theoretical features as well as its experimental results, paving the way for both quantum enhanced biosensing and, hopefully in the future, relativistic testing on massless particles.