Multi-directional controlled quantum teleportation by using nine-qubit entangled state as a single quantum channel (Englisch)

Multi-directional quantum teleportation among the various quantum nodes within a quantum network signifies a crucial step towards the evolution of futuristic quantum internet. In the present study, we examined critically a protocol previously proposed by Choudhary and Dhara [Int. J. Theor. Phys. 57, 1–8 (2017)] for simultaneous transmission of an arbitrary two-qubit information state and two arbitrary single qubit information states between different quantum nodes by employing a ten-qubit entangled state as a single quantum channel. Impeccably, it may be observed that their communication protocol involves three senders and three receivers in which only one receiver needs the permission of controller to reconstruct information (input) state while two receivers may recover input information states without the permissions of the controller. Thus in their protocol, out of three teleportation processes, only one is controlled. However, such quantum communication protocol can be converted into more secure protocol by making control over all the three teleportation processes. We have unequivocally demonstrated that such quantum tasks of teleporting simultaneously an arbitrary two-qubit information state and two arbitrary single qubit information states under the supervision of a controller can be accomplished by using a nine-qubit entangled state as a single quantum channel. In our proposed novel protocol all the three quantum teleportation processes are governed by the controller and hence it possesses more security features. Additionally, our proposed novel protocol requires reduction in entangling qubits in quantum channel and, therefore, enhances the communication efficiency.