Squeezed light via cascaded quadratic processes
Squeezed light is a key resource for the implementation of quantum information protocols, as well as for pushing the precision limit of measurements below the shot noise limit, and represents a valuable source for fundamental testes on quantum mechanics. A squeezed state is defined by the reduction of the uncertainty on one observable below the corresponding uncertainty on the vacuum state, at the expense of an increased uncertainty on the conjugate observable. In Parametric Downconversion processes occurring in χ(2) nonlinear media, Twin Beams (TBs) can be generated which are squeezed in their intensity difference. We produce TBs by pumping a Lithium Niobate crystal with a laser @1064 nm, inducing a second harmonic generation @532 nm, which is efficiently downconverted in sidebands around the pumping wavelength, being the crystal placed in a cavity resonant for both the pump and second harmonic. We measured the squeezing level of the beams up to -5 dB.
Higher order modes squeezing
Coming soon.