  In this paper, we propose a protocol to prepare W states with superconducting
quantum interference devices (SQUID) by using dressed states. Through choosing
a set of dressed states suitably, the protocol can be used to accelerate the
adiabatic passages while additional couplings are unnecessary. Moreover, we can
optimize the evolution of the system with the restraint to the populations of
the intermediate states by choosing suitable controlled parameters. Numerical
simulations show that the protocol is robust against the parameter variations
and decoherence mechanisms. Furthermore, the protocol is faster and more robust
against the dephasing, compared with that by the adiabatic passages. As for the
Rabi frequencies of pulses designed by the method, they can be expressed by the
linear superpositions of Gaussian functions, which does not increase
difficulties to the experiments. In addition, the protocol could be controlled
and manipulated easily in experiments with a circuit quantum electrodynamics
system.
