Arbitrary atomic cluster state concentration for one-way quantum computation

The cluster state is of fundamental importance in one-way quantum computation, but it is fragile in practical noisy environments. In this paper, we describe a method for distilling the maximally entangled atomic cluster state from the arbitrary less-entangled atomic cluster state. During the entire protocol, we only require one pair of less-entangled atomic cluster state and some auxiliary single atoms. Interestingly, the less-entangled atomic cluster state and the auxiliary single atoms do not interact with each other directly. By setting the robust coherent state as the input-output of the low-Q cavities, the concentration task can be achieved. Moreover, the total success probability can be increased by repeating the whole process. This entanglement concentration protocol may have practical applications in one-way quantum computation. (C) 2014 Optical Society of America