Entanglement concentration for arbitrary hybrid less-entangled state and W state using quantum dots and microcavity coupled system

We propose a practical entanglement concentration protocol (ECP) for a hybrid entangled state using quantum dots and microcavity coupled system. A hybrid less-entangled state can be concentrated to a most-entangled state with a certain probability using only one ancillary single photon. Moreover, using this protocol, we can also concentrate arbitrary three-particle less-entangled W state using two ancillary photons and classical communication. The proposed protocols provide us with a useful method to concentrate less-entangled states, which can be implemented with current technology.