  Based on correlations of coherently displaced photon-numbers, we derive
entanglement criteria for the purpose to verify non-Gaussian entanglement. Our
construction method enables us to verify bipartite and multipartite
entanglement of complex states of light. An important advantage of our
technique is that the certified entanglement even persists in the presence of
arbitrarily high, constant losses. We exploit experimental correlation schemes
for the two-mode and multimode scenarios, which allow us to directly measure
the desired observables. To detect entanglement of a given state, a genetic
algorithm is applied to optimize over the infinite set of our constructed
witnesses. In particular, we provide suitable witnesses for several distinct
two-mode states. Moreover, a mixed non-Gaussian four-mode state is shown to be
entangled in all possible non-trivial partitions.
