Quadrature squeezing in the nondegenerate parametric
amplifier

M. Fernee, P. Kinsler, P.D. Drummond

    Department of Physics
    University of Queensland
    Queensland 4072
    Australia

    Phys. Rev. A 51, 864 (1995). 

The squeezing generated in a lossless nondegenerate
parametric amplifier with pump quantisation has been
numerically simulated in a previous paper [G. Drobny and I.
Jex, Phys. Rev. A46, 499 (1992)]. They report squeezing in
a quadrature of up to 90%. We give analytic and numerical
results that show that the quadratures studied by Drobny
and Jex do not exhibit squeezing if the standard technique
of homodyne detection is employed. This is simply shown by
a calculation that reveals that the variance in both
quadratures is equal for all times. On the other hand, if
homomdyne detection is not used, the variance would
oscillate at the optical carrier frequency - hence,
squeezing would be unobservable.We believe that this
illustrates the importance of using analytical and physical
checks of computer-generated results.  





Email: Dr.Paul.Kinsler@physics.org