Adaptive Detection of Arbitrarily Shaped Ultrashort Quantum Light States

First we investigate the generation of non-classical states of light by means of pulsed parametric down-conversion, and second their complete diagnostics and characterisation by means of pulsed homodyne detection. We introduce a new characterisation technique of quantum states of light (starting with the case of the single photon) that combines techniques from the fields of quantum optics and ultrafast coherent control: the idea is to generate femtosecond quantum light states with a broad spectrum, and then, through adaptive mapping of their spectro/temporal mode onto the reference field, to completely retrieve the "shape" of the state under investigation, even with no prior information at hand. The possibility of accessing the arbitrarily-shaped spectro/temporal structure of ultrashort quantum light states will allow a leap forward to the encoding and manipulation of quantum information.