  We study the entanglement distillation in continuous variable systems when a
photon replacement protocol is employed. A cascaded protocol is studied and we
find that the resultant entanglement increases by increasing the number of
repetitions. Interestingly, the entanglement enhancement is not sensitive to
the asymmetry of the protocol and gives the same result for any arrangement in
the absence of loss. The non-Gaussianity of the outcome state is also studied
and it is found that the non-Gaussianity of the state dramatically depends on
the experimental arrangements. By providing practical information on photon
replacement operation, this work is one step towards realization of universal
quantum computation. In particular, in setups where deGaussifying protocols are
only applicable to one of the parties.
