  Highly entangled states called cluster states are a universal resource for
measurement-based quantum computing (QC). Here we propose an efficient method
for producing large cluster states using superconducting quantum circuits. We
show that a large cluster state can be efficiently generated in just one step
by turning on the inter-qubit coupling for a short time. Because the
inter-qubit coupling is only switched on during the time interval for
generating the cluster state, our approach is also convenient for preparing the
initial state for each qubit and for implementing one-way QC via single-qubit
measurements. Moreover, the cluster state is robust against parameter
variations.
