We introduce a suit of simple entangling protocols for generating tripartite GHZ and W states in systems with anisotropic exchange interaction g(XX+YY)+g'ZZ. An interesting example is provided by macroscopic entanglement in Josephson phase qubits with capacitive (g'=0) and inductive (0<|g'/g|<0.1) couplings.
@article{arxiv.0804.3159,
title = {Maximally entangling tripartite protocols for Josephson phase qubits},
author = {Andrei Galiautdinov and John M. Martinis},
journal= {arXiv preprint arXiv:0804.3159},
year = {2009}
}