Implementing a non-local SWAP operation on two entangled pairs by a three-qubit entangled state and a Bell state

We propose a theoretical scheme for the implementation of a non-local quantum SWAP operation on two spatially separated entangled pairs by a three-qubit entangled state and a Bell state, and we show that the operation can swap two qubits of these entangled pairs. The feature of the scheme is that a third side is included, who may participate the process of quantum non-local implementation as a supervisor. Furthermore, when the quantum channel is partially entangled, the third one can rectify the state distorted by imperfect quantum channel.