  Josephson junctions have been shown to be a promising solid-state system for
implementation of quantum computation. The significant two-qubit gates are
generally realized by the capacitive coupling between the nearest neighbour
qubits. We propose an effective Hamiltonian to describe charge qubits coupled
through the cavity. We find that nontrivial two-qubit gates may be achieved by
this coupling. The ability to interconvert localized charge qubits and flying
qubits in the proposed scheme implies that quantum network can be constructed
using this large scalable solid-state system.
