Maximally entangling tripartite protocols for Josephson phase qubits
Andrei Galiautdinov, John M. Martinis · Physical Review A · 2008
We introduce a suit of simple entangling protocols for generating tripartite Greenberger-Horne-Zeilinger and W states in systems with anisotropic exchange interaction $g(XX+YY)+\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{g}ZZ$. An interesting example is provided by macroscopic entanglement in Josephson phase qubits with capacitive $(\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{g}=0)$ and inductive $(0<\ensuremath{\mid}\stackrel{\ifmmode \tilde{}\else \~{}\fi{}}{g}∕g\ensuremath{\mid}<0.1)$ couplings.