SQUEEZED-LIGHT GENERATION BY MEANS OF CASCADED 2ND-ORDER NONLINEARITY

This paper shows that the experimental configuration for self-diffraction experiments can be applied to squeezed light (SL) generation. Nonlinear processes arising from cascading of the second order chi((2)) nonlinearity are responsible for the pump waves squeezing far from the perfect phase matching points for second harmonic and sum frequency generation. The operation of squeezing is performed by interference of co-travelling waves which depending on phase matching conditions for the cascaded processes, are affected either by self-phase modulation (SPM) (as in the nonlinear Mach-Zehnder interferometer) or by cross-phase modulation (CPM) (as in the type-II phase matched second harmonic generation scheme). Since large values of induced third order nonlinearities chi(ind)((3)) are manifested in the presence of cascaded chi((2)), this scheme of SL generation may be of great practical interest. Diffracted waves may also be used to create squeezed vacuum.