Minimum total noise is a measure of higher order squeezing

The possibility of observing higher order squeezing in different optical processes, such as six-wave mixing and four-wave mixing, has been studied and it is shown that amplitude squared squeezing appears in all these cases. It is also shown that the minimum total noise (Tmin) of a higher order squeezed state, which is a measure of the total fluctuations in the field amplitude, always increases with the increase in depth of nonclassicality associated with higher order squeezing. Thus we can use Tmin as an indirect measure of higher order squeezing.