Generation of amplitude-squared squeezed states by combination of up and down degenerate parametric processes

The squeezing of amplitude-squared states in the fundamental mode during th e process of degenerate parametric down conversion has been studied. It is shown that a hybrid of degenerate up and down parametric processes leads to amplitude - squared squeezing in the newly generated fundamental mode with out accompanying sub- poissonian photon statistics. In the process of secon d harmonic generation, a coherent second harmonic results which may be used as reference for homodyning.