  Some non-classical properties such as squeezing, sub-Poissonian photon
statistics or oscillations in photon-number distributions may survive longer in
a phase-sensitive environment than in a phase-insensitive environment. We
examine if entanglement, which is an inter-mode non-classical feature, can also
survive longer in a phase-sensitive environment. Differently from the
single-mode case, we find that making the environment phase-sensitive does not
aid in prolonging entanglement.
