Degaussification of twin-beam and nonlocality in the phase space
  We show that inconclusive photon subtraction (IPS) on twin-beam produces non-Gaussian states that violate Bell's inequality in the phase-space. The violation is larger than for the twin-beam itself irrespective of the IPS quantum efficiency. The explicit expression of IPS map is given both for the density matrix and the Wigner function representations. 
Stefano Olivares and Matteo G. A. Paris