Bidirectional Controlled Teleportation of Two-qubit and Three-qubit State via Nine-qubit Entangled State

In this paper, a bidirectional controlled quantum teleportation via a nine-qubit entangled state is given. In this scheme, Alice wants to teleport a two-qubit entangled state to Bob and Bob wants to teleport arbitrary three-qubit state to Alice at the same time. The quantum teleportation is supervised by a controller. We firstly product a nine-qubit entangled states by the states |000000000⟩, and then we use this entangled states as quantum channel to transfer quantum information along three nodes. This scheme is efficient and economical because the intrinsic efficiency reaches 5/19.